net/ipv6/route.c

   1 /*
   2  *      Linux INET6 implementation
   3  *      FIB front-end.
   4  *
   5  *      Authors:
   6  *      Pedro Roque             <roque@di.fc.ul.pt>
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  */
  13
  14 /*      Changes:
  15  *
  16  *      YOSHIFUJI Hideaki @USAGI
  17  *              reworked default router selection.
  18  *              - respect outgoing interface
  19  *              - select from (probably) reachable routers (i.e.
  20  *              routers in REACHABLE, STALE, DELAY or PROBE states).
  21  *              - always select the same router if it is (probably)
  22  *              reachable.  otherwise, round-robin the list.
  23  *      Ville Nuorvala
  24  *              Fixed routing subtrees.
  25  */
  26
  27 #define pr_fmt(fmt) "IPv6: " fmt
  28
  29 #include <linux/capability.h>
  30 #include <linux/errno.h>
  31 #include <linux/export.h>
  32 #include <linux/types.h>
  33 #include <linux/times.h>
  34 #include <linux/socket.h>
  35 #include <linux/sockios.h>
  36 #include <linux/net.h>
  37 #include <linux/route.h>
  38 #include <linux/netdevice.h>
  39 #include <linux/in6.h>
  40 #include <linux/mroute6.h>
  41 #include <linux/init.h>
  42 #include <linux/if_arp.h>
  43 #include <linux/proc_fs.h>
  44 #include <linux/seq_file.h>
  45 #include <linux/nsproxy.h>
  46 #include <linux/slab.h>
  47 #include <net/net_namespace.h>
  48 #include <net/snmp.h>
  49 #include <net/ipv6.h>
  50 #include <net/ip6_fib.h>
  51 #include <net/ip6_route.h>
  52 #include <net/ndisc.h>
  53 #include <net/addrconf.h>
  54 #include <net/tcp.h>
  55 #include <linux/rtnetlink.h>
  56 #include <net/dst.h>
  57 #include <net/dst_metadata.h>
  58 #include <net/xfrm.h>
  59 #include <net/netevent.h>
  60 #include <net/netlink.h>
  61 #include <net/nexthop.h>
  62 #include <net/lwtunnel.h>
  63 #include <net/ip_tunnels.h>
  64
  65 #include <asm/uaccess.h>
  66
  67 #ifdef CONFIG_SYSCTL
  68 #include <linux/sysctl.h>
  69 #endif
  70
  71 enum rt6_nud_state {
  72         RT6_NUD_FAIL_HARD = -3,
  73         RT6_NUD_FAIL_PROBE = -2,
  74         RT6_NUD_FAIL_DO_RR = -1,
  75         RT6_NUD_SUCCEED = 1
  76 };
  77
  78 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort);
  79 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie);
  80 static unsigned int      ip6_default_advmss(const struct dst_entry *dst);
  81 static unsigned int      ip6_mtu(const struct dst_entry *dst);
  82 static struct dst_entry *ip6_negative_advice(struct dst_entry *);
  83 static void             ip6_dst_destroy(struct dst_entry *);
  84 static void             ip6_dst_ifdown(struct dst_entry *,
  85                                        struct net_device *dev, int how);
  86 static int               ip6_dst_gc(struct dst_ops *ops);
  87
  88 static int              ip6_pkt_discard(struct sk_buff *skb);
  89 static int              ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb);
  90 static int              ip6_pkt_prohibit(struct sk_buff *skb);
  91 static int              ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb);
  92 static void             ip6_link_failure(struct sk_buff *skb);
  93 static void             ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
  94                                            struct sk_buff *skb, u32 mtu);
  95 static void             rt6_do_redirect(struct dst_entry *dst, struct sock *sk,
  96                                         struct sk_buff *skb);
  97 static void             rt6_dst_from_metrics_check(struct rt6_info *rt);
  98 static int rt6_score_route(struct rt6_info *rt, int oif, int strict);
  99
 100 #ifdef CONFIG_IPV6_ROUTE_INFO
 101 static struct rt6_info *rt6_add_route_info(struct net *net,
 102                                            const struct in6_addr *prefix, int prefixlen,
 103                                            const struct in6_addr *gwaddr, int ifindex,
 104                                            unsigned int pref);
 105 static struct rt6_info *rt6_get_route_info(struct net *net,
 106                                            const struct in6_addr *prefix, int prefixlen,
 107                                            const struct in6_addr *gwaddr, int ifindex);
 108 #endif
 109
 110 struct uncached_list {
 111         spinlock_t              lock;
 112         struct list_head        head;
 113 };
 114
 115 static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt6_uncached_list);
 116
 117 static void rt6_uncached_list_add(struct rt6_info *rt)
 118 {
 119         struct uncached_list *ul = raw_cpu_ptr(&rt6_uncached_list);
 120
 121         rt->dst.flags |= DST_NOCACHE;
 122         rt->rt6i_uncached_list = ul;
 123
 124         spin_lock_bh(&ul->lock);
 125         list_add_tail(&rt->rt6i_uncached, &ul->head);
 126         spin_unlock_bh(&ul->lock);
 127 }
 128
 129 static void rt6_uncached_list_del(struct rt6_info *rt)
 130 {
 131         if (!list_empty(&rt->rt6i_uncached)) {
 132                 struct uncached_list *ul = rt->rt6i_uncached_list;
 133
 134                 spin_lock_bh(&ul->lock);
 135                 list_del(&rt->rt6i_uncached);
 136                 spin_unlock_bh(&ul->lock);
 137         }
 138 }
 139
 140 static void rt6_uncached_list_flush_dev(struct net *net, struct net_device *dev)
 141 {
 142         struct net_device *loopback_dev = net->loopback_dev;
 143         int cpu;
 144
 145         for_each_possible_cpu(cpu) {
 146                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
 147                 struct rt6_info *rt;
 148
 149                 spin_lock_bh(&ul->lock);
 150                 list_for_each_entry(rt, &ul->head, rt6i_uncached) {
 151                         struct inet6_dev *rt_idev = rt->rt6i_idev;
 152                         struct net_device *rt_dev = rt->dst.dev;
 153
 154                         if (rt_idev && (rt_idev->dev == dev || !dev) &&
 155                             rt_idev->dev != loopback_dev) {
 156                                 rt->rt6i_idev = in6_dev_get(loopback_dev);
 157                                 in6_dev_put(rt_idev);
 158                         }
 159
 160                         if (rt_dev && (rt_dev == dev || !dev) &&
 161                             rt_dev != loopback_dev) {
 162                                 rt->dst.dev = loopback_dev;
 163                                 dev_hold(rt->dst.dev);
 164                                 dev_put(rt_dev);
 165                         }
 166                 }
 167                 spin_unlock_bh(&ul->lock);
 168         }
 169 }
 170
 171 static u32 *rt6_pcpu_cow_metrics(struct rt6_info *rt)
 172 {
 173         return dst_metrics_write_ptr(rt->dst.from);
 174 }
 175
 176 static u32 *ipv6_cow_metrics(struct dst_entry *dst, unsigned long old)
 177 {
 178         struct rt6_info *rt = (struct rt6_info *)dst;
 179
 180         if (rt->rt6i_flags & RTF_PCPU)
 181                 return rt6_pcpu_cow_metrics(rt);
 182         else if (rt->rt6i_flags & RTF_CACHE)
 183                 return NULL;
 184         else
 185                 return dst_cow_metrics_generic(dst, old);
 186 }
 187
 188 static inline const void *choose_neigh_daddr(struct rt6_info *rt,
 189                                              struct sk_buff *skb,
 190                                              const void *daddr)
 191 {
 192         struct in6_addr *p = &rt->rt6i_gateway;
 193
 194         if (!ipv6_addr_any(p))
 195                 return (const void *) p;
 196         else if (skb)
 197                 return &ipv6_hdr(skb)->daddr;
 198         return daddr;
 199 }
 200
 201 static struct neighbour *ip6_neigh_lookup(const struct dst_entry *dst,
 202                                           struct sk_buff *skb,
 203                                           const void *daddr)
 204 {
 205         struct rt6_info *rt = (struct rt6_info *) dst;
 206         struct neighbour *n;
 207
 208         daddr = choose_neigh_daddr(rt, skb, daddr);
 209         n = __ipv6_neigh_lookup(dst->dev, daddr);
 210         if (n)
 211                 return n;
 212         return neigh_create(&nd_tbl, daddr, dst->dev);
 213 }
 214
 215 static struct dst_ops ip6_dst_ops_template = {
 216         .family                 =       AF_INET6,
 217         .gc                     =       ip6_dst_gc,
 218         .gc_thresh              =       1024,
 219         .check                  =       ip6_dst_check,
 220         .default_advmss         =       ip6_default_advmss,
 221         .mtu                    =       ip6_mtu,
 222         .cow_metrics            =       ipv6_cow_metrics,
 223         .destroy                =       ip6_dst_destroy,
 224         .ifdown                 =       ip6_dst_ifdown,
 225         .negative_advice        =       ip6_negative_advice,
 226         .link_failure           =       ip6_link_failure,
 227         .update_pmtu            =       ip6_rt_update_pmtu,
 228         .redirect               =       rt6_do_redirect,
 229         .local_out              =       __ip6_local_out,
 230         .neigh_lookup           =       ip6_neigh_lookup,
 231 };
 232
 233 static unsigned int ip6_blackhole_mtu(const struct dst_entry *dst)
 234 {
 235         unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 236
 237         return mtu ? : dst->dev->mtu;
 238 }
 239
 240 static void ip6_rt_blackhole_update_pmtu(struct dst_entry *dst, struct sock *sk,
 241                                          struct sk_buff *skb, u32 mtu)
 242 {
 243 }
 244
 245 static void ip6_rt_blackhole_redirect(struct dst_entry *dst, struct sock *sk,
 246                                       struct sk_buff *skb)
 247 {
 248 }
 249
 250 static u32 *ip6_rt_blackhole_cow_metrics(struct dst_entry *dst,
 251                                          unsigned long old)
 252 {
 253         return NULL;
 254 }
 255
 256 static struct dst_ops ip6_dst_blackhole_ops = {
 257         .family                 =       AF_INET6,
 258         .destroy                =       ip6_dst_destroy,
 259         .check                  =       ip6_dst_check,
 260         .mtu                    =       ip6_blackhole_mtu,
 261         .default_advmss         =       ip6_default_advmss,
 262         .update_pmtu            =       ip6_rt_blackhole_update_pmtu,
 263         .redirect               =       ip6_rt_blackhole_redirect,
 264         .cow_metrics            =       ip6_rt_blackhole_cow_metrics,
 265         .neigh_lookup           =       ip6_neigh_lookup,
 266 };
 267
 268 static const u32 ip6_template_metrics[RTAX_MAX] = {
 269         [RTAX_HOPLIMIT - 1] = 0,
 270 };
 271
 272 static const struct rt6_info ip6_null_entry_template = {
 273         .dst = {
 274                 .__refcnt       = ATOMIC_INIT(1),
 275                 .__use          = 1,
 276                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 277                 .error          = -ENETUNREACH,
 278                 .input          = ip6_pkt_discard,
 279                 .output         = ip6_pkt_discard_out,
 280         },
 281         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 282         .rt6i_protocol  = RTPROT_KERNEL,
 283         .rt6i_metric    = ~(u32) 0,
 284         .rt6i_ref       = ATOMIC_INIT(1),
 285 };
 286
 287 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
 288
 289 static const struct rt6_info ip6_prohibit_entry_template = {
 290         .dst = {
 291                 .__refcnt       = ATOMIC_INIT(1),
 292                 .__use          = 1,
 293                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 294                 .error          = -EACCES,
 295                 .input          = ip6_pkt_prohibit,
 296                 .output         = ip6_pkt_prohibit_out,
 297         },
 298         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 299         .rt6i_protocol  = RTPROT_KERNEL,
 300         .rt6i_metric    = ~(u32) 0,
 301         .rt6i_ref       = ATOMIC_INIT(1),
 302 };
 303
 304 static const struct rt6_info ip6_blk_hole_entry_template = {
 305         .dst = {
 306                 .__refcnt       = ATOMIC_INIT(1),
 307                 .__use          = 1,
 308                 .obsolete       = DST_OBSOLETE_FORCE_CHK,
 309                 .error          = -EINVAL,
 310                 .input          = dst_discard,
 311                 .output         = dst_discard_sk,
 312         },
 313         .rt6i_flags     = (RTF_REJECT | RTF_NONEXTHOP),
 314         .rt6i_protocol  = RTPROT_KERNEL,
 315         .rt6i_metric    = ~(u32) 0,
 316         .rt6i_ref       = ATOMIC_INIT(1),
 317 };
 318
 319 #endif
 320
 321 /* allocate dst with ip6_dst_ops */
 322 static struct rt6_info *__ip6_dst_alloc(struct net *net,
 323                                         struct net_device *dev,
 324                                         int flags)
 325 {
 326         struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
 327                                         0, DST_OBSOLETE_FORCE_CHK, flags);
 328
 329         if (rt) {
 330                 struct dst_entry *dst = &rt->dst;
 331
 332                 memset(dst + 1, 0, sizeof(*rt) - sizeof(*dst));
 333                 INIT_LIST_HEAD(&rt->rt6i_siblings);
 334                 INIT_LIST_HEAD(&rt->rt6i_uncached);
 335         }
 336         return rt;
 337 }
 338
 339 static struct rt6_info *ip6_dst_alloc(struct net *net,
 340                                       struct net_device *dev,
 341                                       int flags)
 342 {
 343         struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
 344
 345         if (rt) {
 346                 rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
 347                 if (rt->rt6i_pcpu) {
 348                         int cpu;
 349
 350                         for_each_possible_cpu(cpu) {
 351                                 struct rt6_info **p;
 352
 353                                 p = per_cpu_ptr(rt->rt6i_pcpu, cpu);
 354                                 /* no one shares rt */
 355                                 *p =  NULL;
 356                         }
 357                 } else {
 358                         dst_destroy((struct dst_entry *)rt);
 359                         return NULL;
 360                 }
 361         }
 362
 363         return rt;
 364 }
 365
 366 static void ip6_dst_destroy(struct dst_entry *dst)
 367 {
 368         struct rt6_info *rt = (struct rt6_info *)dst;
 369         struct dst_entry *from = dst->from;
 370         struct inet6_dev *idev;
 371
 372         dst_destroy_metrics_generic(dst);
 373         free_percpu(rt->rt6i_pcpu);
 374         rt6_uncached_list_del(rt);
 375
 376         idev = rt->rt6i_idev;
 377         if (idev) {
 378                 rt->rt6i_idev = NULL;
 379                 in6_dev_put(idev);
 380         }
 381
 382         dst->from = NULL;
 383         dst_release(from);
 384 }
 385
 386 static void ip6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 387                            int how)
 388 {
 389         struct rt6_info *rt = (struct rt6_info *)dst;
 390         struct inet6_dev *idev = rt->rt6i_idev;
 391         struct net_device *loopback_dev =
 392                 dev_net(dev)->loopback_dev;
 393
 394         if (dev != loopback_dev) {
 395                 if (idev && idev->dev == dev) {
 396                         struct inet6_dev *loopback_idev =
 397                                 in6_dev_get(loopback_dev);
 398                         if (loopback_idev) {
 399                                 rt->rt6i_idev = loopback_idev;
 400                                 in6_dev_put(idev);
 401                         }
 402                 }
 403         }
 404 }
 405
 406 static bool rt6_check_expired(const struct rt6_info *rt)
 407 {
 408         if (rt->rt6i_flags & RTF_EXPIRES) {
 409                 if (time_after(jiffies, rt->dst.expires))
 410                         return true;
 411         } else if (rt->dst.from) {
 412                 return rt6_check_expired((struct rt6_info *) rt->dst.from);
 413         }
 414         return false;
 415 }
 416
 417 /* Multipath route selection:
 418  *   Hash based function using packet header and flowlabel.
 419  * Adapted from fib_info_hashfn()
 420  */
 421 static int rt6_info_hash_nhsfn(unsigned int candidate_count,
 422                                const struct flowi6 *fl6)
 423 {
 424         unsigned int val = fl6->flowi6_proto;
 425
 426         val ^= ipv6_addr_hash(&fl6->daddr);
 427         val ^= ipv6_addr_hash(&fl6->saddr);
 428
 429         /* Work only if this not encapsulated */
 430         switch (fl6->flowi6_proto) {
 431         case IPPROTO_UDP:
 432         case IPPROTO_TCP:
 433         case IPPROTO_SCTP:
 434                 val ^= (__force u16)fl6->fl6_sport;
 435                 val ^= (__force u16)fl6->fl6_dport;
 436                 break;
 437
 438         case IPPROTO_ICMPV6:
 439                 val ^= (__force u16)fl6->fl6_icmp_type;
 440                 val ^= (__force u16)fl6->fl6_icmp_code;
 441                 break;
 442         }
 443         /* RFC6438 recommands to use flowlabel */
 444         val ^= (__force u32)fl6->flowlabel;
 445
 446         /* Perhaps, we need to tune, this function? */
 447         val = val ^ (val >> 7) ^ (val >> 12);
 448         return val % candidate_count;
 449 }
 450
 451 static struct rt6_info *rt6_multipath_select(struct rt6_info *match,
 452                                              struct flowi6 *fl6, int oif,
 453                                              int strict)
 454 {
 455         struct rt6_info *sibling, *next_sibling;
 456         int route_choosen;
 457
 458         route_choosen = rt6_info_hash_nhsfn(match->rt6i_nsiblings + 1, fl6);
 459         /* Don't change the route, if route_choosen == 0
 460          * (siblings does not include ourself)
 461          */
 462         if (route_choosen)
 463                 list_for_each_entry_safe(sibling, next_sibling,
 464                                 &match->rt6i_siblings, rt6i_siblings) {
 465                         route_choosen--;
 466                         if (route_choosen == 0) {
 467                                 if (rt6_score_route(sibling, oif, strict) < 0)
 468                                         break;
 469                                 match = sibling;
 470                                 break;
 471                         }
 472                 }
 473         return match;
 474 }
 475
 476 /*
 477  *      Route lookup. Any table->tb6_lock is implied.
 478  */
 479
 480 static inline struct rt6_info *rt6_device_match(struct net *net,
 481                                                     struct rt6_info *rt,
 482                                                     const struct in6_addr *saddr,
 483                                                     int oif,
 484                                                     int flags)
 485 {
 486         struct rt6_info *local = NULL;
 487         struct rt6_info *sprt;
 488
 489         if (!oif && ipv6_addr_any(saddr))
 490                 goto out;
 491
 492         for (sprt = rt; sprt; sprt = sprt->dst.rt6_next) {
 493                 struct net_device *dev = sprt->dst.dev;
 494
 495                 if (oif) {
 496                         if (dev->ifindex == oif)
 497                                 return sprt;
 498                         if (dev->flags & IFF_LOOPBACK) {
 499                                 if (!sprt->rt6i_idev ||
 500                                     sprt->rt6i_idev->dev->ifindex != oif) {
 501                                         if (flags & RT6_LOOKUP_F_IFACE && oif)
 502                                                 continue;
 503                                         if (local && (!oif ||
 504                                                       local->rt6i_idev->dev->ifindex == oif))
 505                                                 continue;
 506                                 }
 507                                 local = sprt;
 508                         }
 509                 } else {
 510                         if (ipv6_chk_addr(net, saddr, dev,
 511                                           flags & RT6_LOOKUP_F_IFACE))
 512                                 return sprt;
 513                 }
 514         }
 515
 516         if (oif) {
 517                 if (local)
 518                         return local;
 519
 520                 if (flags & RT6_LOOKUP_F_IFACE)
 521                         return net->ipv6.ip6_null_entry;
 522         }
 523 out:
 524         return rt;
 525 }
 526
 527 #ifdef CONFIG_IPV6_ROUTER_PREF
 528 struct __rt6_probe_work {
 529         struct work_struct work;
 530         struct in6_addr target;
 531         struct net_device *dev;
 532 };
 533
 534 static void rt6_probe_deferred(struct work_struct *w)
 535 {
 536         struct in6_addr mcaddr;
 537         struct __rt6_probe_work *work =
 538                 container_of(w, struct __rt6_probe_work, work);
 539
 540         addrconf_addr_solict_mult(&work->target, &mcaddr);
 541         ndisc_send_ns(work->dev, NULL, &work->target, &mcaddr, NULL, NULL);
 542         dev_put(work->dev);
 543         kfree(work);
 544 }
 545
 546 static void rt6_probe(struct rt6_info *rt)
 547 {
 548         struct __rt6_probe_work *work;
 549         struct neighbour *neigh;
 550         /*
 551          * Okay, this does not seem to be appropriate
 552          * for now, however, we need to check if it
 553          * is really so; aka Router Reachability Probing.
 554          *
 555          * Router Reachability Probe MUST be rate-limited
 556          * to no more than one per minute.
 557          */
 558         if (!rt || !(rt->rt6i_flags & RTF_GATEWAY))
 559                 return;
 560         rcu_read_lock_bh();
 561         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 562         if (neigh) {
 563                 if (neigh->nud_state & NUD_VALID)
 564                         goto out;
 565
 566                 work = NULL;
 567                 write_lock(&neigh->lock);
 568                 if (!(neigh->nud_state & NUD_VALID) &&
 569                     time_after(jiffies,
 570                                neigh->updated +
 571                                rt->rt6i_idev->cnf.rtr_probe_interval)) {
 572                         work = kmalloc(sizeof(*work), GFP_ATOMIC);
 573                         if (work)
 574                                 __neigh_set_probe_once(neigh);
 575                 }
 576                 write_unlock(&neigh->lock);
 577         } else {
 578                 work = kmalloc(sizeof(*work), GFP_ATOMIC);
 579         }
 580
 581         if (work) {
 582                 INIT_WORK(&work->work, rt6_probe_deferred);
 583                 work->target = rt->rt6i_gateway;
 584                 dev_hold(rt->dst.dev);
 585                 work->dev = rt->dst.dev;
 586                 schedule_work(&work->work);
 587         }
 588
 589 out:
 590         rcu_read_unlock_bh();
 591 }
 592 #else
 593 static inline void rt6_probe(struct rt6_info *rt)
 594 {
 595 }
 596 #endif
 597
 598 /*
 599  * Default Router Selection (RFC 2461 6.3.6)
 600  */
 601 static inline int rt6_check_dev(struct rt6_info *rt, int oif)
 602 {
 603         struct net_device *dev = rt->dst.dev;
 604         if (!oif || dev->ifindex == oif)
 605                 return 2;
 606         if ((dev->flags & IFF_LOOPBACK) &&
 607             rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
 608                 return 1;
 609         return 0;
 610 }
 611
 612 static inline enum rt6_nud_state rt6_check_neigh(struct rt6_info *rt)
 613 {
 614         struct neighbour *neigh;
 615         enum rt6_nud_state ret = RT6_NUD_FAIL_HARD;
 616
 617         if (rt->rt6i_flags & RTF_NONEXTHOP ||
 618             !(rt->rt6i_flags & RTF_GATEWAY))
 619                 return RT6_NUD_SUCCEED;
 620
 621         rcu_read_lock_bh();
 622         neigh = __ipv6_neigh_lookup_noref(rt->dst.dev, &rt->rt6i_gateway);
 623         if (neigh) {
 624                 read_lock(&neigh->lock);
 625                 if (neigh->nud_state & NUD_VALID)
 626                         ret = RT6_NUD_SUCCEED;
 627 #ifdef CONFIG_IPV6_ROUTER_PREF
 628                 else if (!(neigh->nud_state & NUD_FAILED))
 629                         ret = RT6_NUD_SUCCEED;
 630                 else
 631                         ret = RT6_NUD_FAIL_PROBE;
 632 #endif
 633                 read_unlock(&neigh->lock);
 634         } else {
 635                 ret = IS_ENABLED(CONFIG_IPV6_ROUTER_PREF) ?
 636                       RT6_NUD_SUCCEED : RT6_NUD_FAIL_DO_RR;
 637         }
 638         rcu_read_unlock_bh();
 639
 640         return ret;
 641 }
 642
 643 static int rt6_score_route(struct rt6_info *rt, int oif,
 644                            int strict)
 645 {
 646         int m;
 647
 648         m = rt6_check_dev(rt, oif);
 649         if (!m && (strict & RT6_LOOKUP_F_IFACE))
 650                 return RT6_NUD_FAIL_HARD;
 651 #ifdef CONFIG_IPV6_ROUTER_PREF
 652         m |= IPV6_DECODE_PREF(IPV6_EXTRACT_PREF(rt->rt6i_flags)) << 2;
 653 #endif
 654         if (strict & RT6_LOOKUP_F_REACHABLE) {
 655                 int n = rt6_check_neigh(rt);
 656                 if (n < 0)
 657                         return n;
 658         }
 659         return m;
 660 }
 661
 662 static struct rt6_info *find_match(struct rt6_info *rt, int oif, int strict,
 663                                    int *mpri, struct rt6_info *match,
 664                                    bool *do_rr)
 665 {
 666         int m;
 667         bool match_do_rr = false;
 668         struct inet6_dev *idev = rt->rt6i_idev;
 669         struct net_device *dev = rt->dst.dev;
 670
 671         if (dev && !netif_carrier_ok(dev) &&
 672             idev->cnf.ignore_routes_with_linkdown)
 673                 goto out;
 674
 675         if (rt6_check_expired(rt))
 676                 goto out;
 677
 678         m = rt6_score_route(rt, oif, strict);
 679         if (m == RT6_NUD_FAIL_DO_RR) {
 680                 match_do_rr = true;
 681                 m = 0; /* lowest valid score */
 682         } else if (m == RT6_NUD_FAIL_HARD) {
 683                 goto out;
 684         }
 685
 686         if (strict & RT6_LOOKUP_F_REACHABLE)
 687                 rt6_probe(rt);
 688
 689         /* note that m can be RT6_NUD_FAIL_PROBE at this point */
 690         if (m > *mpri) {
 691                 *do_rr = match_do_rr;
 692                 *mpri = m;
 693                 match = rt;
 694         }
 695 out:
 696         return match;
 697 }
 698
 699 static struct rt6_info *find_rr_leaf(struct fib6_node *fn,
 700                                      struct rt6_info *rr_head,
 701                                      u32 metric, int oif, int strict,
 702                                      bool *do_rr)
 703 {
 704         struct rt6_info *rt, *match, *cont;
 705         int mpri = -1;
 706
 707         match = NULL;
 708         cont = NULL;
 709         for (rt = rr_head; rt; rt = rt->dst.rt6_next) {
 710                 if (rt->rt6i_metric != metric) {
 711                         cont = rt;
 712                         break;
 713                 }
 714
 715                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 716         }
 717
 718         for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) {
 719                 if (rt->rt6i_metric != metric) {
 720                         cont = rt;
 721                         break;
 722                 }
 723
 724                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 725         }
 726
 727         if (match || !cont)
 728                 return match;
 729
 730         for (rt = cont; rt; rt = rt->dst.rt6_next)
 731                 match = find_match(rt, oif, strict, &mpri, match, do_rr);
 732
 733         return match;
 734 }
 735
 736 static struct rt6_info *rt6_select(struct fib6_node *fn, int oif, int strict)
 737 {
 738         struct rt6_info *match, *rt0;
 739         struct net *net;
 740         bool do_rr = false;
 741
 742         rt0 = fn->rr_ptr;
 743         if (!rt0)
 744                 fn->rr_ptr = rt0 = fn->leaf;
 745
 746         match = find_rr_leaf(fn, rt0, rt0->rt6i_metric, oif, strict,
 747                              &do_rr);
 748
 749         if (do_rr) {
 750                 struct rt6_info *next = rt0->dst.rt6_next;
 751
 752                 /* no entries matched; do round-robin */
 753                 if (!next || next->rt6i_metric != rt0->rt6i_metric)
 754                         next = fn->leaf;
 755
 756                 if (next != rt0)
 757                         fn->rr_ptr = next;
 758         }
 759
 760         net = dev_net(rt0->dst.dev);
 761         return match ? match : net->ipv6.ip6_null_entry;
 762 }
 763
 764 static bool rt6_is_gw_or_nonexthop(const struct rt6_info *rt)
 765 {
 766         return (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY));
 767 }
 768
 769 #ifdef CONFIG_IPV6_ROUTE_INFO
 770 int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
 771                   const struct in6_addr *gwaddr)
 772 {
 773         struct net *net = dev_net(dev);
 774         struct route_info *rinfo = (struct route_info *) opt;
 775         struct in6_addr prefix_buf, *prefix;
 776         unsigned int pref;
 777         unsigned long lifetime;
 778         struct rt6_info *rt;
 779
 780         if (len < sizeof(struct route_info)) {
 781                 return -EINVAL;
 782         }
 783
 784         /* Sanity check for prefix_len and length */
 785         if (rinfo->length > 3) {
 786                 return -EINVAL;
 787         } else if (rinfo->prefix_len > 128) {
 788                 return -EINVAL;
 789         } else if (rinfo->prefix_len > 64) {
 790                 if (rinfo->length < 2) {
 791                         return -EINVAL;
 792                 }
 793         } else if (rinfo->prefix_len > 0) {
 794                 if (rinfo->length < 1) {
 795                         return -EINVAL;
 796                 }
 797         }
 798
 799         pref = rinfo->route_pref;
 800         if (pref == ICMPV6_ROUTER_PREF_INVALID)
 801                 return -EINVAL;
 802
 803         lifetime = addrconf_timeout_fixup(ntohl(rinfo->lifetime), HZ);
 804
 805         if (rinfo->length == 3)
 806                 prefix = (struct in6_addr *)rinfo->prefix;
 807         else {
 808                 /* this function is safe */
 809                 ipv6_addr_prefix(&prefix_buf,
 810                                  (struct in6_addr *)rinfo->prefix,
 811                                  rinfo->prefix_len);
 812                 prefix = &prefix_buf;
 813         }
 814
 815         if (rinfo->prefix_len == 0)
 816                 rt = rt6_get_dflt_router(gwaddr, dev);
 817         else
 818                 rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
 819                                         gwaddr, dev->ifindex);
 820
 821         if (rt && !lifetime) {
 822                 ip6_del_rt(rt);
 823                 rt = NULL;
 824         }
 825
 826         if (!rt && lifetime)
 827                 rt = rt6_add_route_info(net, prefix, rinfo->prefix_len, gwaddr, dev->ifindex,
 828                                         pref);
 829         else if (rt)
 830                 rt->rt6i_flags = RTF_ROUTEINFO |
 831                                  (rt->rt6i_flags & ~RTF_PREF_MASK) | RTF_PREF(pref);
 832
 833         if (rt) {
 834                 if (!addrconf_finite_timeout(lifetime))
 835                         rt6_clean_expires(rt);
 836                 else
 837                         rt6_set_expires(rt, jiffies + HZ * lifetime);
 838
 839                 ip6_rt_put(rt);
 840         }
 841         return 0;
 842 }
 843 #endif
 844
 845 static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
 846                                         struct in6_addr *saddr)
 847 {
 848         struct fib6_node *pn;
 849         while (1) {
 850                 if (fn->fn_flags & RTN_TL_ROOT)
 851                         return NULL;
 852                 pn = fn->parent;
 853                 if (FIB6_SUBTREE(pn) && FIB6_SUBTREE(pn) != fn)
 854                         fn = fib6_lookup(FIB6_SUBTREE(pn), NULL, saddr);
 855                 else
 856                         fn = pn;
 857                 if (fn->fn_flags & RTN_RTINFO)
 858                         return fn;
 859         }
 860 }
 861
 862 static struct rt6_info *ip6_pol_route_lookup(struct net *net,
 863                                              struct fib6_table *table,
 864                                              struct flowi6 *fl6, int flags)
 865 {
 866         struct fib6_node *fn;
 867         struct rt6_info *rt;
 868
 869         read_lock_bh(&table->tb6_lock);
 870         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
 871 restart:
 872         rt = fn->leaf;
 873         rt = rt6_device_match(net, rt, &fl6->saddr, fl6->flowi6_oif, flags);
 874         if (rt->rt6i_nsiblings && fl6->flowi6_oif == 0)
 875                 rt = rt6_multipath_select(rt, fl6, fl6->flowi6_oif, flags);
 876         if (rt == net->ipv6.ip6_null_entry) {
 877                 fn = fib6_backtrack(fn, &fl6->saddr);
 878                 if (fn)
 879                         goto restart;
 880         }
 881         dst_use(&rt->dst, jiffies);
 882         read_unlock_bh(&table->tb6_lock);
 883         return rt;
 884
 885 }
 886
 887 struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
 888                                     int flags)
 889 {
 890         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_lookup);
 891 }
 892 EXPORT_SYMBOL_GPL(ip6_route_lookup);
 893
 894 struct rt6_info *rt6_lookup(struct net *net, const struct in6_addr *daddr,
 895                             const struct in6_addr *saddr, int oif, int strict)
 896 {
 897         struct flowi6 fl6 = {
 898                 .flowi6_oif = oif,
 899                 .daddr = *daddr,
 900         };
 901         struct dst_entry *dst;
 902         int flags = strict ? RT6_LOOKUP_F_IFACE : 0;
 903
 904         if (saddr) {
 905                 memcpy(&fl6.saddr, saddr, sizeof(*saddr));
 906                 flags |= RT6_LOOKUP_F_HAS_SADDR;
 907         }
 908
 909         dst = fib6_rule_lookup(net, &fl6, flags, ip6_pol_route_lookup);
 910         if (dst->error == 0)
 911                 return (struct rt6_info *) dst;
 912
 913         dst_release(dst);
 914
 915         return NULL;
 916 }
 917 EXPORT_SYMBOL(rt6_lookup);
 918
 919 /* ip6_ins_rt is called with FREE table->tb6_lock.
 920    It takes new route entry, the addition fails by any reason the
 921    route is freed. In any case, if caller does not hold it, it may
 922    be destroyed.
 923  */
 924
 925 static int __ip6_ins_rt(struct rt6_info *rt, struct nl_info *info,
 926                         struct mx6_config *mxc)
 927 {
 928         int err;
 929         struct fib6_table *table;
 930
 931         table = rt->rt6i_table;
 932         write_lock_bh(&table->tb6_lock);
 933         err = fib6_add(&table->tb6_root, rt, info, mxc);
 934         write_unlock_bh(&table->tb6_lock);
 935
 936         return err;
 937 }
 938
 939 int ip6_ins_rt(struct rt6_info *rt)
 940 {
 941         struct nl_info info = { .nl_net = dev_net(rt->dst.dev), };
 942         struct mx6_config mxc = { .mx = NULL, };
 943
 944         return __ip6_ins_rt(rt, &info, &mxc);
 945 }
 946
 947 static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
 948                                            const struct in6_addr *daddr,
 949                                            const struct in6_addr *saddr)
 950 {
 951         struct rt6_info *rt;
 952
 953         /*
 954          *      Clone the route.
 955          */
 956
 957         if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
 958                 ort = (struct rt6_info *)ort->dst.from;
 959
 960         rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
 961
 962         if (!rt)
 963                 return NULL;
 964
 965         ip6_rt_copy_init(rt, ort);
 966         rt->rt6i_flags |= RTF_CACHE;
 967         rt->rt6i_metric = 0;
 968         rt->dst.flags |= DST_HOST;
 969         rt->rt6i_dst.addr = *daddr;
 970         rt->rt6i_dst.plen = 128;
 971
 972         if (!rt6_is_gw_or_nonexthop(ort)) {
 973                 if (ort->rt6i_dst.plen != 128 &&
 974                     ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
 975                         rt->rt6i_flags |= RTF_ANYCAST;
 976 #ifdef CONFIG_IPV6_SUBTREES
 977                 if (rt->rt6i_src.plen && saddr) {
 978                         rt->rt6i_src.addr = *saddr;
 979                         rt->rt6i_src.plen = 128;
 980                 }
 981 #endif
 982         }
 983
 984         return rt;
 985 }
 986
 987 static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
 988 {
 989         struct rt6_info *pcpu_rt;
 990
 991         pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
 992                                   rt->dst.dev, rt->dst.flags);
 993
 994         if (!pcpu_rt)
 995                 return NULL;
 996         ip6_rt_copy_init(pcpu_rt, rt);
 997         pcpu_rt->rt6i_protocol = rt->rt6i_protocol;
 998         pcpu_rt->rt6i_flags |= RTF_PCPU;
 999         return pcpu_rt;
1000 }
1001
1002 /* It should be called with read_lock_bh(&tb6_lock) acquired */
1003 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
1004 {
1005         struct rt6_info *pcpu_rt, **p;
1006
1007         p = this_cpu_ptr(rt->rt6i_pcpu);
1008         pcpu_rt = *p;
1009
1010         if (pcpu_rt) {
1011                 dst_hold(&pcpu_rt->dst);
1012                 rt6_dst_from_metrics_check(pcpu_rt);
1013         }
1014         return pcpu_rt;
1015 }
1016
1017 static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
1018 {
1019         struct fib6_table *table = rt->rt6i_table;
1020         struct rt6_info *pcpu_rt, *prev, **p;
1021
1022         pcpu_rt = ip6_rt_pcpu_alloc(rt);
1023         if (!pcpu_rt) {
1024                 struct net *net = dev_net(rt->dst.dev);
1025
1026                 dst_hold(&net->ipv6.ip6_null_entry->dst);
1027                 return net->ipv6.ip6_null_entry;
1028         }
1029
1030         read_lock_bh(&table->tb6_lock);
1031         if (rt->rt6i_pcpu) {
1032                 p = this_cpu_ptr(rt->rt6i_pcpu);
1033                 prev = cmpxchg(p, NULL, pcpu_rt);
1034                 if (prev) {
1035                         /* If someone did it before us, return prev instead */
1036                         dst_destroy(&pcpu_rt->dst);
1037                         pcpu_rt = prev;
1038                 }
1039         } else {
1040                 /* rt has been removed from the fib6 tree
1041                  * before we have a chance to acquire the read_lock.
1042                  * In this case, don't brother to create a pcpu rt
1043                  * since rt is going away anyway.  The next
1044                  * dst_check() will trigger a re-lookup.
1045                  */
1046                 dst_destroy(&pcpu_rt->dst);
1047                 pcpu_rt = rt;
1048         }
1049         dst_hold(&pcpu_rt->dst);
1050         rt6_dst_from_metrics_check(pcpu_rt);
1051         read_unlock_bh(&table->tb6_lock);
1052         return pcpu_rt;
1053 }
1054
1055 static struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table, int oif,
1056                                       struct flowi6 *fl6, int flags)
1057 {
1058         struct fib6_node *fn, *saved_fn;
1059         struct rt6_info *rt;
1060         int strict = 0;
1061
1062         strict |= flags & RT6_LOOKUP_F_IFACE;
1063         if (net->ipv6.devconf_all->forwarding == 0)
1064                 strict |= RT6_LOOKUP_F_REACHABLE;
1065
1066         read_lock_bh(&table->tb6_lock);
1067
1068         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1069         saved_fn = fn;
1070
1071 redo_rt6_select:
1072         rt = rt6_select(fn, oif, strict);
1073         if (rt->rt6i_nsiblings)
1074                 rt = rt6_multipath_select(rt, fl6, oif, strict);
1075         if (rt == net->ipv6.ip6_null_entry) {
1076                 fn = fib6_backtrack(fn, &fl6->saddr);
1077                 if (fn)
1078                         goto redo_rt6_select;
1079                 else if (strict & RT6_LOOKUP_F_REACHABLE) {
1080                         /* also consider unreachable route */
1081                         strict &= ~RT6_LOOKUP_F_REACHABLE;
1082                         fn = saved_fn;
1083                         goto redo_rt6_select;
1084                 }
1085         }
1086
1087
1088         if (rt == net->ipv6.ip6_null_entry || (rt->rt6i_flags & RTF_CACHE)) {
1089                 dst_use(&rt->dst, jiffies);
1090                 read_unlock_bh(&table->tb6_lock);
1091
1092                 rt6_dst_from_metrics_check(rt);
1093                 return rt;
1094         } else if (unlikely((fl6->flowi6_flags & FLOWI_FLAG_KNOWN_NH) &&
1095                             !(rt->rt6i_flags & RTF_GATEWAY))) {
1096                 /* Create a RTF_CACHE clone which will not be
1097                  * owned by the fib6 tree.  It is for the special case where
1098                  * the daddr in the skb during the neighbor look-up is different
1099                  * from the fl6->daddr used to look-up route here.
1100                  */
1101
1102                 struct rt6_info *uncached_rt;
1103
1104                 dst_use(&rt->dst, jiffies);
1105                 read_unlock_bh(&table->tb6_lock);
1106
1107                 uncached_rt = ip6_rt_cache_alloc(rt, &fl6->daddr, NULL);
1108                 dst_release(&rt->dst);
1109
1110                 if (uncached_rt)
1111                         rt6_uncached_list_add(uncached_rt);
1112                 else
1113                         uncached_rt = net->ipv6.ip6_null_entry;
1114
1115                 dst_hold(&uncached_rt->dst);
1116                 return uncached_rt;
1117
1118         } else {
1119                 /* Get a percpu copy */
1120
1121                 struct rt6_info *pcpu_rt;
1122
1123                 rt->dst.lastuse = jiffies;
1124                 rt->dst.__use++;
1125                 pcpu_rt = rt6_get_pcpu_route(rt);
1126
1127                 if (pcpu_rt) {
1128                         read_unlock_bh(&table->tb6_lock);
1129                 } else {
1130                         /* We have to do the read_unlock first
1131                          * because rt6_make_pcpu_route() may trigger
1132                          * ip6_dst_gc() which will take the write_lock.
1133                          */
1134                         dst_hold(&rt->dst);
1135                         read_unlock_bh(&table->tb6_lock);
1136                         pcpu_rt = rt6_make_pcpu_route(rt);
1137                         dst_release(&rt->dst);
1138                 }
1139
1140                 return pcpu_rt;
1141
1142         }
1143 }
1144
1145 static struct rt6_info *ip6_pol_route_input(struct net *net, struct fib6_table *table,
1146                                             struct flowi6 *fl6, int flags)
1147 {
1148         return ip6_pol_route(net, table, fl6->flowi6_iif, fl6, flags);
1149 }
1150
1151 static struct dst_entry *ip6_route_input_lookup(struct net *net,
1152                                                 struct net_device *dev,
1153                                                 struct flowi6 *fl6, int flags)
1154 {
1155         if (rt6_need_strict(&fl6->daddr) && dev->type != ARPHRD_PIMREG)
1156                 flags |= RT6_LOOKUP_F_IFACE;
1157
1158         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_input);
1159 }
1160
1161 void ip6_route_input(struct sk_buff *skb)
1162 {
1163         const struct ipv6hdr *iph = ipv6_hdr(skb);
1164         struct net *net = dev_net(skb->dev);
1165         int flags = RT6_LOOKUP_F_HAS_SADDR;
1166         struct ip_tunnel_info *tun_info;
1167         struct flowi6 fl6 = {
1168                 .flowi6_iif = skb->dev->ifindex,
1169                 .daddr = iph->daddr,
1170                 .saddr = iph->saddr,
1171                 .flowlabel = ip6_flowinfo(iph),
1172                 .flowi6_mark = skb->mark,
1173                 .flowi6_proto = iph->nexthdr,
1174         };
1175
1176         tun_info = skb_tunnel_info(skb);
1177         if (tun_info && !(tun_info->mode & IP_TUNNEL_INFO_TX))
1178                 fl6.flowi6_tun_key.tun_id = tun_info->key.tun_id;
1179         skb_dst_drop(skb);
1180         skb_dst_set(skb, ip6_route_input_lookup(net, skb->dev, &fl6, flags));
1181 }
1182
1183 static struct rt6_info *ip6_pol_route_output(struct net *net, struct fib6_table *table,
1184                                              struct flowi6 *fl6, int flags)
1185 {
1186         return ip6_pol_route(net, table, fl6->flowi6_oif, fl6, flags);
1187 }
1188
1189 struct dst_entry *ip6_route_output(struct net *net, const struct sock *sk,
1190                                     struct flowi6 *fl6)
1191 {
1192         int flags = 0;
1193
1194         fl6->flowi6_iif = LOOPBACK_IFINDEX;
1195
1196         if ((sk && sk->sk_bound_dev_if) || rt6_need_strict(&fl6->daddr))
1197                 flags |= RT6_LOOKUP_F_IFACE;
1198
1199         if (!ipv6_addr_any(&fl6->saddr))
1200                 flags |= RT6_LOOKUP_F_HAS_SADDR;
1201         else if (sk)
1202                 flags |= rt6_srcprefs2flags(inet6_sk(sk)->srcprefs);
1203
1204         return fib6_rule_lookup(net, fl6, flags, ip6_pol_route_output);
1205 }
1206 EXPORT_SYMBOL(ip6_route_output);
1207
1208 struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
1209 {
1210         struct rt6_info *rt, *ort = (struct rt6_info *) dst_orig;
1211         struct dst_entry *new = NULL;
1212
1213         rt = dst_alloc(&ip6_dst_blackhole_ops, ort->dst.dev, 1, DST_OBSOLETE_NONE, 0);
1214         if (rt) {
1215                 new = &rt->dst;
1216
1217                 memset(new + 1, 0, sizeof(*rt) - sizeof(*new));
1218
1219                 new->__use = 1;
1220                 new->input = dst_discard;
1221                 new->output = dst_discard_sk;
1222
1223                 if (dst_metrics_read_only(&ort->dst))
1224                         new->_metrics = ort->dst._metrics;
1225                 else
1226                         dst_copy_metrics(new, &ort->dst);
1227                 rt->rt6i_idev = ort->rt6i_idev;
1228                 if (rt->rt6i_idev)
1229                         in6_dev_hold(rt->rt6i_idev);
1230
1231                 rt->rt6i_gateway = ort->rt6i_gateway;
1232                 rt->rt6i_flags = ort->rt6i_flags;
1233                 rt->rt6i_metric = 0;
1234
1235                 memcpy(&rt->rt6i_dst, &ort->rt6i_dst, sizeof(struct rt6key));
1236 #ifdef CONFIG_IPV6_SUBTREES
1237                 memcpy(&rt->rt6i_src, &ort->rt6i_src, sizeof(struct rt6key));
1238 #endif
1239
1240                 dst_free(new);
1241         }
1242
1243         dst_release(dst_orig);
1244         return new ? new : ERR_PTR(-ENOMEM);
1245 }
1246
1247 /*
1248  *      Destination cache support functions
1249  */
1250
1251 static void rt6_dst_from_metrics_check(struct rt6_info *rt)
1252 {
1253         if (rt->dst.from &&
1254             dst_metrics_ptr(&rt->dst) != dst_metrics_ptr(rt->dst.from))
1255                 dst_init_metrics(&rt->dst, dst_metrics_ptr(rt->dst.from), true);
1256 }
1257
1258 static struct dst_entry *rt6_check(struct rt6_info *rt, u32 cookie)
1259 {
1260         if (!rt->rt6i_node || (rt->rt6i_node->fn_sernum != cookie))
1261                 return NULL;
1262
1263         if (rt6_check_expired(rt))
1264                 return NULL;
1265
1266         return &rt->dst;
1267 }
1268
1269 static struct dst_entry *rt6_dst_from_check(struct rt6_info *rt, u32 cookie)
1270 {
1271         if (rt->dst.obsolete == DST_OBSOLETE_FORCE_CHK &&
1272             rt6_check((struct rt6_info *)(rt->dst.from), cookie))
1273                 return &rt->dst;
1274         else
1275                 return NULL;
1276 }
1277
1278 static struct dst_entry *ip6_dst_check(struct dst_entry *dst, u32 cookie)
1279 {
1280         struct rt6_info *rt;
1281
1282         rt = (struct rt6_info *) dst;
1283
1284         /* All IPV6 dsts are created with ->obsolete set to the value
1285          * DST_OBSOLETE_FORCE_CHK which forces validation calls down
1286          * into this function always.
1287          */
1288
1289         rt6_dst_from_metrics_check(rt);
1290
1291         if ((rt->rt6i_flags & RTF_PCPU) || unlikely(dst->flags & DST_NOCACHE))
1292                 return rt6_dst_from_check(rt, cookie);
1293         else
1294                 return rt6_check(rt, cookie);
1295 }
1296
1297 static struct dst_entry *ip6_negative_advice(struct dst_entry *dst)
1298 {
1299         struct rt6_info *rt = (struct rt6_info *) dst;
1300
1301         if (rt) {
1302                 if (rt->rt6i_flags & RTF_CACHE) {
1303                         if (rt6_check_expired(rt)) {
1304                                 ip6_del_rt(rt);
1305                                 dst = NULL;
1306                         }
1307                 } else {
1308                         dst_release(dst);
1309                         dst = NULL;
1310                 }
1311         }
1312         return dst;
1313 }
1314
1315 static void ip6_link_failure(struct sk_buff *skb)
1316 {
1317         struct rt6_info *rt;
1318
1319         icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_ADDR_UNREACH, 0);
1320
1321         rt = (struct rt6_info *) skb_dst(skb);
1322         if (rt) {
1323                 if (rt->rt6i_flags & RTF_CACHE) {
1324                         dst_hold(&rt->dst);
1325                         if (ip6_del_rt(rt))
1326                                 dst_free(&rt->dst);
1327                 } else if (rt->rt6i_node && (rt->rt6i_flags & RTF_DEFAULT)) {
1328                         rt->rt6i_node->fn_sernum = -1;
1329                 }
1330         }
1331 }
1332
1333 static void rt6_do_update_pmtu(struct rt6_info *rt, u32 mtu)
1334 {
1335         struct net *net = dev_net(rt->dst.dev);
1336
1337         rt->rt6i_flags |= RTF_MODIFIED;
1338         rt->rt6i_pmtu = mtu;
1339         rt6_update_expires(rt, net->ipv6.sysctl.ip6_rt_mtu_expires);
1340 }
1341
1342 static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk,
1343                                  const struct ipv6hdr *iph, u32 mtu)
1344 {
1345         struct rt6_info *rt6 = (struct rt6_info *)dst;
1346
1347         if (rt6->rt6i_flags & RTF_LOCAL)
1348                 return;
1349
1350         dst_confirm(dst);
1351         mtu = max_t(u32, mtu, IPV6_MIN_MTU);
1352         if (mtu >= dst_mtu(dst))
1353                 return;
1354
1355         if (rt6->rt6i_flags & RTF_CACHE) {
1356                 rt6_do_update_pmtu(rt6, mtu);
1357         } else {
1358                 const struct in6_addr *daddr, *saddr;
1359                 struct rt6_info *nrt6;
1360
1361                 if (iph) {
1362                         daddr = &iph->daddr;
1363                         saddr = &iph->saddr;
1364                 } else if (sk) {
1365                         daddr = &sk->sk_v6_daddr;
1366                         saddr = &inet6_sk(sk)->saddr;
1367                 } else {
1368                         return;
1369                 }
1370                 nrt6 = ip6_rt_cache_alloc(rt6, daddr, saddr);
1371                 if (nrt6) {
1372                         rt6_do_update_pmtu(nrt6, mtu);
1373
1374                         /* ip6_ins_rt(nrt6) will bump the
1375                          * rt6->rt6i_node->fn_sernum
1376                          * which will fail the next rt6_check() and
1377                          * invalidate the sk->sk_dst_cache.
1378                          */
1379                         ip6_ins_rt(nrt6);
1380                 }
1381         }
1382 }
1383
1384 static void ip6_rt_update_pmtu(struct dst_entry *dst, struct sock *sk,
1385                                struct sk_buff *skb, u32 mtu)
1386 {
1387         __ip6_rt_update_pmtu(dst, sk, skb ? ipv6_hdr(skb) : NULL, mtu);
1388 }
1389
1390 void ip6_update_pmtu(struct sk_buff *skb, struct net *net, __be32 mtu,
1391                      int oif, u32 mark)
1392 {
1393         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1394         struct dst_entry *dst;
1395         struct flowi6 fl6;
1396
1397         memset(&fl6, 0, sizeof(fl6));
1398         fl6.flowi6_oif = oif;
1399         fl6.flowi6_mark = mark ? mark : IP6_REPLY_MARK(net, skb->mark);
1400         fl6.daddr = iph->daddr;
1401         fl6.saddr = iph->saddr;
1402         fl6.flowlabel = ip6_flowinfo(iph);
1403
1404         dst = ip6_route_output(net, NULL, &fl6);
1405         if (!dst->error)
1406                 __ip6_rt_update_pmtu(dst, NULL, iph, ntohl(mtu));
1407         dst_release(dst);
1408 }
1409 EXPORT_SYMBOL_GPL(ip6_update_pmtu);
1410
1411 void ip6_sk_update_pmtu(struct sk_buff *skb, struct sock *sk, __be32 mtu)
1412 {
1413         ip6_update_pmtu(skb, sock_net(sk), mtu,
1414                         sk->sk_bound_dev_if, sk->sk_mark);
1415 }
1416 EXPORT_SYMBOL_GPL(ip6_sk_update_pmtu);
1417
1418 /* Handle redirects */
1419 struct ip6rd_flowi {
1420         struct flowi6 fl6;
1421         struct in6_addr gateway;
1422 };
1423
1424 static struct rt6_info *__ip6_route_redirect(struct net *net,
1425                                              struct fib6_table *table,
1426                                              struct flowi6 *fl6,
1427                                              int flags)
1428 {
1429         struct ip6rd_flowi *rdfl = (struct ip6rd_flowi *)fl6;
1430         struct rt6_info *rt;
1431         struct fib6_node *fn;
1432
1433         /* Get the "current" route for this destination and
1434          * check if the redirect has come from approriate router.
1435          *
1436          * RFC 4861 specifies that redirects should only be
1437          * accepted if they come from the nexthop to the target.
1438          * Due to the way the routes are chosen, this notion
1439          * is a bit fuzzy and one might need to check all possible
1440          * routes.
1441          */
1442
1443         read_lock_bh(&table->tb6_lock);
1444         fn = fib6_lookup(&table->tb6_root, &fl6->daddr, &fl6->saddr);
1445 restart:
1446         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1447                 if (rt6_check_expired(rt))
1448                         continue;
1449                 if (rt->dst.error)
1450                         break;
1451                 if (!(rt->rt6i_flags & RTF_GATEWAY))
1452                         continue;
1453                 if (fl6->flowi6_oif != rt->dst.dev->ifindex)
1454                         continue;
1455                 if (!ipv6_addr_equal(&rdfl->gateway, &rt->rt6i_gateway))
1456                         continue;
1457                 break;
1458         }
1459
1460         if (!rt)
1461                 rt = net->ipv6.ip6_null_entry;
1462         else if (rt->dst.error) {
1463                 rt = net->ipv6.ip6_null_entry;
1464                 goto out;
1465         }
1466
1467         if (rt == net->ipv6.ip6_null_entry) {
1468                 fn = fib6_backtrack(fn, &fl6->saddr);
1469                 if (fn)
1470                         goto restart;
1471         }
1472
1473 out:
1474         dst_hold(&rt->dst);
1475
1476         read_unlock_bh(&table->tb6_lock);
1477
1478         return rt;
1479 };
1480
1481 static struct dst_entry *ip6_route_redirect(struct net *net,
1482                                         const struct flowi6 *fl6,
1483                                         const struct in6_addr *gateway)
1484 {
1485         int flags = RT6_LOOKUP_F_HAS_SADDR;
1486         struct ip6rd_flowi rdfl;
1487
1488         rdfl.fl6 = *fl6;
1489         rdfl.gateway = *gateway;
1490
1491         return fib6_rule_lookup(net, &rdfl.fl6,
1492                                 flags, __ip6_route_redirect);
1493 }
1494
1495 void ip6_redirect(struct sk_buff *skb, struct net *net, int oif, u32 mark)
1496 {
1497         const struct ipv6hdr *iph = (struct ipv6hdr *) skb->data;
1498         struct dst_entry *dst;
1499         struct flowi6 fl6;
1500
1501         memset(&fl6, 0, sizeof(fl6));
1502         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1503         fl6.flowi6_oif = oif;
1504         fl6.flowi6_mark = mark;
1505         fl6.daddr = iph->daddr;
1506         fl6.saddr = iph->saddr;
1507         fl6.flowlabel = ip6_flowinfo(iph);
1508
1509         dst = ip6_route_redirect(net, &fl6, &ipv6_hdr(skb)->saddr);
1510         rt6_do_redirect(dst, NULL, skb);
1511         dst_release(dst);
1512 }
1513 EXPORT_SYMBOL_GPL(ip6_redirect);
1514
1515 void ip6_redirect_no_header(struct sk_buff *skb, struct net *net, int oif,
1516                             u32 mark)
1517 {
1518         const struct ipv6hdr *iph = ipv6_hdr(skb);
1519         const struct rd_msg *msg = (struct rd_msg *)icmp6_hdr(skb);
1520         struct dst_entry *dst;
1521         struct flowi6 fl6;
1522
1523         memset(&fl6, 0, sizeof(fl6));
1524         fl6.flowi6_iif = LOOPBACK_IFINDEX;
1525         fl6.flowi6_oif = oif;
1526         fl6.flowi6_mark = mark;
1527         fl6.daddr = msg->dest;
1528         fl6.saddr = iph->daddr;
1529
1530         dst = ip6_route_redirect(net, &fl6, &iph->saddr);
1531         rt6_do_redirect(dst, NULL, skb);
1532         dst_release(dst);
1533 }
1534
1535 void ip6_sk_redirect(struct sk_buff *skb, struct sock *sk)
1536 {
1537         ip6_redirect(skb, sock_net(sk), sk->sk_bound_dev_if, sk->sk_mark);
1538 }
1539 EXPORT_SYMBOL_GPL(ip6_sk_redirect);
1540
1541 static unsigned int ip6_default_advmss(const struct dst_entry *dst)
1542 {
1543         struct net_device *dev = dst->dev;
1544         unsigned int mtu = dst_mtu(dst);
1545         struct net *net = dev_net(dev);
1546
1547         mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
1548
1549         if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss)
1550                 mtu = net->ipv6.sysctl.ip6_rt_min_advmss;
1551
1552         /*
1553          * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
1554          * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
1555          * IPV6_MAXPLEN is also valid and means: "any MSS,
1556          * rely only on pmtu discovery"
1557          */
1558         if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
1559                 mtu = IPV6_MAXPLEN;
1560         return mtu;
1561 }
1562
1563 static unsigned int ip6_mtu(const struct dst_entry *dst)
1564 {
1565         const struct rt6_info *rt = (const struct rt6_info *)dst;
1566         unsigned int mtu = rt->rt6i_pmtu;
1567         struct inet6_dev *idev;
1568
1569         if (mtu)
1570                 goto out;
1571
1572         mtu = dst_metric_raw(dst, RTAX_MTU);
1573         if (mtu)
1574                 goto out;
1575
1576         mtu = IPV6_MIN_MTU;
1577
1578         rcu_read_lock();
1579         idev = __in6_dev_get(dst->dev);
1580         if (idev)
1581                 mtu = idev->cnf.mtu6;
1582         rcu_read_unlock();
1583
1584 out:
1585         return min_t(unsigned int, mtu, IP6_MAX_MTU);
1586 }
1587
1588 static struct dst_entry *icmp6_dst_gc_list;
1589 static DEFINE_SPINLOCK(icmp6_dst_lock);
1590
1591 struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
1592                                   struct flowi6 *fl6)
1593 {
1594         struct dst_entry *dst;
1595         struct rt6_info *rt;
1596         struct inet6_dev *idev = in6_dev_get(dev);
1597         struct net *net = dev_net(dev);
1598
1599         if (unlikely(!idev))
1600                 return ERR_PTR(-ENODEV);
1601
1602         rt = ip6_dst_alloc(net, dev, 0);
1603         if (unlikely(!rt)) {
1604                 in6_dev_put(idev);
1605                 dst = ERR_PTR(-ENOMEM);
1606                 goto out;
1607         }
1608
1609         rt->dst.flags |= DST_HOST;
1610         rt->dst.output  = ip6_output;
1611         atomic_set(&rt->dst.__refcnt, 1);
1612         rt->rt6i_gateway  = fl6->daddr;
1613         rt->rt6i_dst.addr = fl6->daddr;
1614         rt->rt6i_dst.plen = 128;
1615         rt->rt6i_idev     = idev;
1616         dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 0);
1617
1618         spin_lock_bh(&icmp6_dst_lock);
1619         rt->dst.next = icmp6_dst_gc_list;
1620         icmp6_dst_gc_list = &rt->dst;
1621         spin_unlock_bh(&icmp6_dst_lock);
1622
1623         fib6_force_start_gc(net);
1624
1625         dst = xfrm_lookup(net, &rt->dst, flowi6_to_flowi(fl6), NULL, 0);
1626
1627 out:
1628         return dst;
1629 }
1630
1631 int icmp6_dst_gc(void)
1632 {
1633         struct dst_entry *dst, **pprev;
1634         int more = 0;
1635
1636         spin_lock_bh(&icmp6_dst_lock);
1637         pprev = &icmp6_dst_gc_list;
1638
1639         while ((dst = *pprev) != NULL) {
1640                 if (!atomic_read(&dst->__refcnt)) {
1641                         *pprev = dst->next;
1642                         dst_free(dst);
1643                 } else {
1644                         pprev = &dst->next;
1645                         ++more;
1646                 }
1647         }
1648
1649         spin_unlock_bh(&icmp6_dst_lock);
1650
1651         return more;
1652 }
1653
1654 static void icmp6_clean_all(int (*func)(struct rt6_info *rt, void *arg),
1655                             void *arg)
1656 {
1657         struct dst_entry *dst, **pprev;
1658
1659         spin_lock_bh(&icmp6_dst_lock);
1660         pprev = &icmp6_dst_gc_list;
1661         while ((dst = *pprev) != NULL) {
1662                 struct rt6_info *rt = (struct rt6_info *) dst;
1663                 if (func(rt, arg)) {
1664                         *pprev = dst->next;
1665                         dst_free(dst);
1666                 } else {
1667                         pprev = &dst->next;
1668                 }
1669         }
1670         spin_unlock_bh(&icmp6_dst_lock);
1671 }
1672
1673 static int ip6_dst_gc(struct dst_ops *ops)
1674 {
1675         struct net *net = container_of(ops, struct net, ipv6.ip6_dst_ops);
1676         int rt_min_interval = net->ipv6.sysctl.ip6_rt_gc_min_interval;
1677         int rt_max_size = net->ipv6.sysctl.ip6_rt_max_size;
1678         int rt_elasticity = net->ipv6.sysctl.ip6_rt_gc_elasticity;
1679         int rt_gc_timeout = net->ipv6.sysctl.ip6_rt_gc_timeout;
1680         unsigned long rt_last_gc = net->ipv6.ip6_rt_last_gc;
1681         int entries;
1682
1683         entries = dst_entries_get_fast(ops);
1684         if (time_after(rt_last_gc + rt_min_interval, jiffies) &&
1685             entries <= rt_max_size)
1686                 goto out;
1687
1688         net->ipv6.ip6_rt_gc_expire++;
1689         fib6_run_gc(net->ipv6.ip6_rt_gc_expire, net, true);
1690         entries = dst_entries_get_slow(ops);
1691         if (entries < ops->gc_thresh)
1692                 net->ipv6.ip6_rt_gc_expire = rt_gc_timeout>>1;
1693 out:
1694         net->ipv6.ip6_rt_gc_expire -= net->ipv6.ip6_rt_gc_expire>>rt_elasticity;
1695         return entries > rt_max_size;
1696 }
1697
1698 static int ip6_convert_metrics(struct mx6_config *mxc,
1699                                const struct fib6_config *cfg)
1700 {
1701         bool ecn_ca = false;
1702         struct nlattr *nla;
1703         int remaining;
1704         u32 *mp;
1705
1706         if (!cfg->fc_mx)
1707                 return 0;
1708
1709         mp = kzalloc(sizeof(u32) * RTAX_MAX, GFP_KERNEL);
1710         if (unlikely(!mp))
1711                 return -ENOMEM;
1712
1713         nla_for_each_attr(nla, cfg->fc_mx, cfg->fc_mx_len, remaining) {
1714                 int type = nla_type(nla);
1715                 u32 val;
1716
1717                 if (!type)
1718                         continue;
1719                 if (unlikely(type > RTAX_MAX))
1720                         goto err;
1721
1722                 if (type == RTAX_CC_ALGO) {
1723                         char tmp[TCP_CA_NAME_MAX];
1724
1725                         nla_strlcpy(tmp, nla, sizeof(tmp));
1726                         val = tcp_ca_get_key_by_name(tmp, &ecn_ca);
1727                         if (val == TCP_CA_UNSPEC)
1728                                 goto err;
1729                 } else {
1730                         val = nla_get_u32(nla);
1731                 }
1732                 if (type == RTAX_FEATURES && (val & ~RTAX_FEATURE_MASK))
1733                         goto err;
1734
1735                 mp[type - 1] = val;
1736                 __set_bit(type - 1, mxc->mx_valid);
1737         }
1738
1739         if (ecn_ca) {
1740                 __set_bit(RTAX_FEATURES - 1, mxc->mx_valid);
1741                 mp[RTAX_FEATURES - 1] |= DST_FEATURE_ECN_CA;
1742         }
1743
1744         mxc->mx = mp;
1745         return 0;
1746  err:
1747         kfree(mp);
1748         return -EINVAL;
1749 }
1750
1751 int ip6_route_info_create(struct fib6_config *cfg, struct rt6_info **rt_ret)
1752 {
1753         int err;
1754         struct net *net = cfg->fc_nlinfo.nl_net;
1755         struct rt6_info *rt = NULL;
1756         struct net_device *dev = NULL;
1757         struct inet6_dev *idev = NULL;
1758         struct fib6_table *table;
1759         int addr_type;
1760
1761         if (cfg->fc_dst_len > 128 || cfg->fc_src_len > 128)
1762                 return -EINVAL;
1763 #ifndef CONFIG_IPV6_SUBTREES
1764         if (cfg->fc_src_len)
1765                 return -EINVAL;
1766 #endif
1767         if (cfg->fc_ifindex) {
1768                 err = -ENODEV;
1769                 dev = dev_get_by_index(net, cfg->fc_ifindex);
1770                 if (!dev)
1771                         goto out;
1772                 idev = in6_dev_get(dev);
1773                 if (!idev)
1774                         goto out;
1775         }
1776
1777         if (cfg->fc_metric == 0)
1778                 cfg->fc_metric = IP6_RT_PRIO_USER;
1779
1780         err = -ENOBUFS;
1781         if (cfg->fc_nlinfo.nlh &&
1782             !(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
1783                 table = fib6_get_table(net, cfg->fc_table);
1784                 if (!table) {
1785                         pr_warn("NLM_F_CREATE should be specified when creating new route\n");
1786                         table = fib6_new_table(net, cfg->fc_table);
1787                 }
1788         } else {
1789                 table = fib6_new_table(net, cfg->fc_table);
1790         }
1791
1792         if (!table)
1793                 goto out;
1794
1795         rt = ip6_dst_alloc(net, NULL,
1796                            (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
1797
1798         if (!rt) {
1799                 err = -ENOMEM;
1800                 goto out;
1801         }
1802
1803         if (cfg->fc_flags & RTF_EXPIRES)
1804                 rt6_set_expires(rt, jiffies +
1805                                 clock_t_to_jiffies(cfg->fc_expires));
1806         else
1807                 rt6_clean_expires(rt);
1808
1809         if (cfg->fc_protocol == RTPROT_UNSPEC)
1810                 cfg->fc_protocol = RTPROT_BOOT;
1811         rt->rt6i_protocol = cfg->fc_protocol;
1812
1813         addr_type = ipv6_addr_type(&cfg->fc_dst);
1814
1815         if (addr_type & IPV6_ADDR_MULTICAST)
1816                 rt->dst.input = ip6_mc_input;
1817         else if (cfg->fc_flags & RTF_LOCAL)
1818                 rt->dst.input = ip6_input;
1819         else
1820                 rt->dst.input = ip6_forward;
1821
1822         rt->dst.output = ip6_output;
1823
1824         if (cfg->fc_encap) {
1825                 struct lwtunnel_state *lwtstate;
1826
1827                 err = lwtunnel_build_state(dev, cfg->fc_encap_type,
1828                                            cfg->fc_encap, AF_INET6, cfg,
1829                                            &lwtstate);
1830                 if (err)
1831                         goto out;
1832                 rt->dst.lwtstate = lwtstate_get(lwtstate);
1833                 if (lwtunnel_output_redirect(rt->dst.lwtstate)) {
1834                         rt->dst.lwtstate->orig_output = rt->dst.output;
1835                         rt->dst.output = lwtunnel_output;
1836                 }
1837                 if (lwtunnel_input_redirect(rt->dst.lwtstate)) {
1838                         rt->dst.lwtstate->orig_input = rt->dst.input;
1839                         rt->dst.input = lwtunnel_input;
1840                 }
1841         }
1842
1843         ipv6_addr_prefix(&rt->rt6i_dst.addr, &cfg->fc_dst, cfg->fc_dst_len);
1844         rt->rt6i_dst.plen = cfg->fc_dst_len;
1845         if (rt->rt6i_dst.plen == 128)
1846                 rt->dst.flags |= DST_HOST;
1847
1848 #ifdef CONFIG_IPV6_SUBTREES
1849         ipv6_addr_prefix(&rt->rt6i_src.addr, &cfg->fc_src, cfg->fc_src_len);
1850         rt->rt6i_src.plen = cfg->fc_src_len;
1851 #endif
1852
1853         rt->rt6i_metric = cfg->fc_metric;
1854
1855         /* We cannot add true routes via loopback here,
1856            they would result in kernel looping; promote them to reject routes
1857          */
1858         if ((cfg->fc_flags & RTF_REJECT) ||
1859             (dev && (dev->flags & IFF_LOOPBACK) &&
1860              !(addr_type & IPV6_ADDR_LOOPBACK) &&
1861              !(cfg->fc_flags & RTF_LOCAL))) {
1862                 /* hold loopback dev/idev if we haven't done so. */
1863                 if (dev != net->loopback_dev) {
1864                         if (dev) {
1865                                 dev_put(dev);
1866                                 in6_dev_put(idev);
1867                         }
1868                         dev = net->loopback_dev;
1869                         dev_hold(dev);
1870                         idev = in6_dev_get(dev);
1871                         if (!idev) {
1872                                 err = -ENODEV;
1873                                 goto out;
1874                         }
1875                 }
1876                 rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
1877                 switch (cfg->fc_type) {
1878                 case RTN_BLACKHOLE:
1879                         rt->dst.error = -EINVAL;
1880                         rt->dst.output = dst_discard_sk;
1881                         rt->dst.input = dst_discard;
1882                         break;
1883                 case RTN_PROHIBIT:
1884                         rt->dst.error = -EACCES;
1885                         rt->dst.output = ip6_pkt_prohibit_out;
1886                         rt->dst.input = ip6_pkt_prohibit;
1887                         break;
1888                 case RTN_THROW:
1889                 default:
1890                         rt->dst.error = (cfg->fc_type == RTN_THROW) ? -EAGAIN
1891                                         : -ENETUNREACH;
1892                         rt->dst.output = ip6_pkt_discard_out;
1893                         rt->dst.input = ip6_pkt_discard;
1894                         break;
1895                 }
1896                 goto install_route;
1897         }
1898
1899         if (cfg->fc_flags & RTF_GATEWAY) {
1900                 const struct in6_addr *gw_addr;
1901                 int gwa_type;
1902
1903                 gw_addr = &cfg->fc_gateway;
1904                 gwa_type = ipv6_addr_type(gw_addr);
1905
1906                 /* if gw_addr is local we will fail to detect this in case
1907                  * address is still TENTATIVE (DAD in progress). rt6_lookup()
1908                  * will return already-added prefix route via interface that
1909                  * prefix route was assigned to, which might be non-loopback.
1910                  */
1911                 err = -EINVAL;
1912                 if (ipv6_chk_addr_and_flags(net, gw_addr,
1913                                             gwa_type & IPV6_ADDR_LINKLOCAL ?
1914                                             dev : NULL, 0, 0))
1915                         goto out;
1916
1917                 rt->rt6i_gateway = *gw_addr;
1918
1919                 if (gwa_type != (IPV6_ADDR_LINKLOCAL|IPV6_ADDR_UNICAST)) {
1920                         struct rt6_info *grt;
1921
1922                         /* IPv6 strictly inhibits using not link-local
1923                            addresses as nexthop address.
1924                            Otherwise, router will not able to send redirects.
1925                            It is very good, but in some (rare!) circumstances
1926                            (SIT, PtP, NBMA NOARP links) it is handy to allow
1927                            some exceptions. --ANK
1928                          */
1929                         if (!(gwa_type & IPV6_ADDR_UNICAST))
1930                                 goto out;
1931
1932                         grt = rt6_lookup(net, gw_addr, NULL, cfg->fc_ifindex, 1);
1933
1934                         err = -EHOSTUNREACH;
1935                         if (!grt)
1936                                 goto out;
1937                         if (dev) {
1938                                 if (dev != grt->dst.dev) {
1939                                         ip6_rt_put(grt);
1940                                         goto out;
1941                                 }
1942                         } else {
1943                                 dev = grt->dst.dev;
1944                                 idev = grt->rt6i_idev;
1945                                 dev_hold(dev);
1946                                 in6_dev_hold(grt->rt6i_idev);
1947                         }
1948                         if (!(grt->rt6i_flags & RTF_GATEWAY))
1949                                 err = 0;
1950                         ip6_rt_put(grt);
1951
1952                         if (err)
1953                                 goto out;
1954                 }
1955                 err = -EINVAL;
1956                 if (!dev || (dev->flags & IFF_LOOPBACK))
1957                         goto out;
1958         }
1959
1960         err = -ENODEV;
1961         if (!dev)
1962                 goto out;
1963
1964         if (!ipv6_addr_any(&cfg->fc_prefsrc)) {
1965                 if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
1966                         err = -EINVAL;
1967                         goto out;
1968                 }
1969                 rt->rt6i_prefsrc.addr = cfg->fc_prefsrc;
1970                 rt->rt6i_prefsrc.plen = 128;
1971         } else
1972                 rt->rt6i_prefsrc.plen = 0;
1973
1974         rt->rt6i_flags = cfg->fc_flags;
1975
1976 install_route:
1977         rt->dst.dev = dev;
1978         rt->rt6i_idev = idev;
1979         rt->rt6i_table = table;
1980
1981         cfg->fc_nlinfo.nl_net = dev_net(dev);
1982
1983         *rt_ret = rt;
1984
1985         return 0;
1986 out:
1987         if (dev)
1988                 dev_put(dev);
1989         if (idev)
1990                 in6_dev_put(idev);
1991         if (rt)
1992                 dst_free(&rt->dst);
1993
1994         *rt_ret = NULL;
1995
1996         return err;
1997 }
1998
1999 int ip6_route_add(struct fib6_config *cfg)
2000 {
2001         struct mx6_config mxc = { .mx = NULL, };
2002         struct rt6_info *rt = NULL;
2003         int err;
2004
2005         err = ip6_route_info_create(cfg, &rt);
2006         if (err)
2007                 goto out;
2008
2009         err = ip6_convert_metrics(&mxc, cfg);
2010         if (err)
2011                 goto out;
2012
2013         err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, &mxc);
2014
2015         kfree(mxc.mx);
2016
2017         return err;
2018 out:
2019         if (rt)
2020                 dst_free(&rt->dst);
2021
2022         return err;
2023 }
2024
2025 static int __ip6_del_rt(struct rt6_info *rt, struct nl_info *info)
2026 {
2027         int err;
2028         struct fib6_table *table;
2029         struct net *net = dev_net(rt->dst.dev);
2030
2031         if (rt == net->ipv6.ip6_null_entry) {
2032                 err = -ENOENT;
2033                 goto out;
2034         }
2035
2036         table = rt->rt6i_table;
2037         write_lock_bh(&table->tb6_lock);
2038         err = fib6_del(rt, info);
2039         write_unlock_bh(&table->tb6_lock);
2040
2041 out:
2042         ip6_rt_put(rt);
2043         return err;
2044 }
2045
2046 int ip6_del_rt(struct rt6_info *rt)
2047 {
2048         struct nl_info info = {
2049                 .nl_net = dev_net(rt->dst.dev),
2050         };
2051         return __ip6_del_rt(rt, &info);
2052 }
2053
2054 static int ip6_route_del(struct fib6_config *cfg)
2055 {
2056         struct fib6_table *table;
2057         struct fib6_node *fn;
2058         struct rt6_info *rt;
2059         int err = -ESRCH;
2060
2061         table = fib6_get_table(cfg->fc_nlinfo.nl_net, cfg->fc_table);
2062         if (!table)
2063                 return err;
2064
2065         read_lock_bh(&table->tb6_lock);
2066
2067         fn = fib6_locate(&table->tb6_root,
2068                          &cfg->fc_dst, cfg->fc_dst_len,
2069                          &cfg->fc_src, cfg->fc_src_len);
2070
2071         if (fn) {
2072                 for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2073                         if ((rt->rt6i_flags & RTF_CACHE) &&
2074                             !(cfg->fc_flags & RTF_CACHE))
2075                                 continue;
2076                         if (cfg->fc_ifindex &&
2077                             (!rt->dst.dev ||
2078                              rt->dst.dev->ifindex != cfg->fc_ifindex))
2079                                 continue;
2080                         if (cfg->fc_flags & RTF_GATEWAY &&
2081                             !ipv6_addr_equal(&cfg->fc_gateway, &rt->rt6i_gateway))
2082                                 continue;
2083                         if (cfg->fc_metric && cfg->fc_metric != rt->rt6i_metric)
2084                                 continue;
2085                         dst_hold(&rt->dst);
2086                         read_unlock_bh(&table->tb6_lock);
2087
2088                         return __ip6_del_rt(rt, &cfg->fc_nlinfo);
2089                 }
2090         }
2091         read_unlock_bh(&table->tb6_lock);
2092
2093         return err;
2094 }
2095
2096 static void rt6_do_redirect(struct dst_entry *dst, struct sock *sk, struct sk_buff *skb)
2097 {
2098         struct net *net = dev_net(skb->dev);
2099         struct netevent_redirect netevent;
2100         struct rt6_info *rt, *nrt = NULL;
2101         struct ndisc_options ndopts;
2102         struct inet6_dev *in6_dev;
2103         struct neighbour *neigh;
2104         struct rd_msg *msg;
2105         int optlen, on_link;
2106         u8 *lladdr;
2107
2108         optlen = skb_tail_pointer(skb) - skb_transport_header(skb);
2109         optlen -= sizeof(*msg);
2110
2111         if (optlen < 0) {
2112                 net_dbg_ratelimited("rt6_do_redirect: packet too short\n");
2113                 return;
2114         }
2115
2116         msg = (struct rd_msg *)icmp6_hdr(skb);
2117
2118         if (ipv6_addr_is_multicast(&msg->dest)) {
2119                 net_dbg_ratelimited("rt6_do_redirect: destination address is multicast\n");
2120                 return;
2121         }
2122
2123         on_link = 0;
2124         if (ipv6_addr_equal(&msg->dest, &msg->target)) {
2125                 on_link = 1;
2126         } else if (ipv6_addr_type(&msg->target) !=
2127                    (IPV6_ADDR_UNICAST|IPV6_ADDR_LINKLOCAL)) {
2128                 net_dbg_ratelimited("rt6_do_redirect: target address is not link-local unicast\n");
2129                 return;
2130         }
2131
2132         in6_dev = __in6_dev_get(skb->dev);
2133         if (!in6_dev)
2134                 return;
2135         if (in6_dev->cnf.forwarding || !in6_dev->cnf.accept_redirects)
2136                 return;
2137
2138         /* RFC2461 8.1:
2139          *      The IP source address of the Redirect MUST be the same as the current
2140          *      first-hop router for the specified ICMP Destination Address.
2141          */
2142
2143         if (!ndisc_parse_options(msg->opt, optlen, &ndopts)) {
2144                 net_dbg_ratelimited("rt6_redirect: invalid ND options\n");
2145                 return;
2146         }
2147
2148         lladdr = NULL;
2149         if (ndopts.nd_opts_tgt_lladdr) {
2150                 lladdr = ndisc_opt_addr_data(ndopts.nd_opts_tgt_lladdr,
2151                                              skb->dev);
2152                 if (!lladdr) {
2153                         net_dbg_ratelimited("rt6_redirect: invalid link-layer address length\n");
2154                         return;
2155                 }
2156         }
2157
2158         rt = (struct rt6_info *) dst;
2159         if (rt == net->ipv6.ip6_null_entry) {
2160                 net_dbg_ratelimited("rt6_redirect: source isn't a valid nexthop for redirect target\n");
2161                 return;
2162         }
2163
2164         /* Redirect received -> path was valid.
2165          * Look, redirects are sent only in response to data packets,
2166          * so that this nexthop apparently is reachable. --ANK
2167          */
2168         dst_confirm(&rt->dst);
2169
2170         neigh = __neigh_lookup(&nd_tbl, &msg->target, skb->dev, 1);
2171         if (!neigh)
2172                 return;
2173
2174         /*
2175          *      We have finally decided to accept it.
2176          */
2177
2178         neigh_update(neigh, lladdr, NUD_STALE,
2179                      NEIGH_UPDATE_F_WEAK_OVERRIDE|
2180                      NEIGH_UPDATE_F_OVERRIDE|
2181                      (on_link ? 0 : (NEIGH_UPDATE_F_OVERRIDE_ISROUTER|
2182                                      NEIGH_UPDATE_F_ISROUTER))
2183                      );
2184
2185         nrt = ip6_rt_cache_alloc(rt, &msg->dest, NULL);
2186         if (!nrt)
2187                 goto out;
2188
2189         nrt->rt6i_flags = RTF_GATEWAY|RTF_UP|RTF_DYNAMIC|RTF_CACHE;
2190         if (on_link)
2191                 nrt->rt6i_flags &= ~RTF_GATEWAY;
2192
2193         nrt->rt6i_gateway = *(struct in6_addr *)neigh->primary_key;
2194
2195         if (ip6_ins_rt(nrt))
2196                 goto out;
2197
2198         netevent.old = &rt->dst;
2199         netevent.new = &nrt->dst;
2200         netevent.daddr = &msg->dest;
2201         netevent.neigh = neigh;
2202         call_netevent_notifiers(NETEVENT_REDIRECT, &netevent);
2203
2204         if (rt->rt6i_flags & RTF_CACHE) {
2205                 rt = (struct rt6_info *) dst_clone(&rt->dst);
2206                 ip6_del_rt(rt);
2207         }
2208
2209 out:
2210         neigh_release(neigh);
2211 }
2212
2213 /*
2214  *      Misc support functions
2215  */
2216
2217 static void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
2218 {
2219         BUG_ON(from->dst.from);
2220
2221         rt->rt6i_flags &= ~RTF_EXPIRES;
2222         dst_hold(&from->dst);
2223         rt->dst.from = &from->dst;
2224         dst_init_metrics(&rt->dst, dst_metrics_ptr(&from->dst), true);
2225 }
2226
2227 static void ip6_rt_copy_init(struct rt6_info *rt, struct rt6_info *ort)
2228 {
2229         rt->dst.input = ort->dst.input;
2230         rt->dst.output = ort->dst.output;
2231         rt->rt6i_dst = ort->rt6i_dst;
2232         rt->dst.error = ort->dst.error;
2233         rt->rt6i_idev = ort->rt6i_idev;
2234         if (rt->rt6i_idev)
2235                 in6_dev_hold(rt->rt6i_idev);
2236         rt->dst.lastuse = jiffies;
2237         rt->rt6i_gateway = ort->rt6i_gateway;
2238         rt->rt6i_flags = ort->rt6i_flags;
2239         rt6_set_from(rt, ort);
2240         rt->rt6i_metric = ort->rt6i_metric;
2241 #ifdef CONFIG_IPV6_SUBTREES
2242         rt->rt6i_src = ort->rt6i_src;
2243 #endif
2244         rt->rt6i_prefsrc = ort->rt6i_prefsrc;
2245         rt->rt6i_table = ort->rt6i_table;
2246         rt->dst.lwtstate = lwtstate_get(ort->dst.lwtstate);
2247 }
2248
2249 #ifdef CONFIG_IPV6_ROUTE_INFO
2250 static struct rt6_info *rt6_get_route_info(struct net *net,
2251                                            const struct in6_addr *prefix, int prefixlen,
2252                                            const struct in6_addr *gwaddr, int ifindex)
2253 {
2254         struct fib6_node *fn;
2255         struct rt6_info *rt = NULL;
2256         struct fib6_table *table;
2257
2258         table = fib6_get_table(net, RT6_TABLE_INFO);
2259         if (!table)
2260                 return NULL;
2261
2262         read_lock_bh(&table->tb6_lock);
2263         fn = fib6_locate(&table->tb6_root, prefix, prefixlen, NULL, 0);
2264         if (!fn)
2265                 goto out;
2266
2267         for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
2268                 if (rt->dst.dev->ifindex != ifindex)
2269                         continue;
2270                 if ((rt->rt6i_flags & (RTF_ROUTEINFO|RTF_GATEWAY)) != (RTF_ROUTEINFO|RTF_GATEWAY))
2271                         continue;
2272                 if (!ipv6_addr_equal(&rt->rt6i_gateway, gwaddr))
2273                         continue;
2274                 dst_hold(&rt->dst);
2275                 break;
2276         }
2277 out:
2278         read_unlock_bh(&table->tb6_lock);
2279         return rt;
2280 }
2281
2282 static struct rt6_info *rt6_add_route_info(struct net *net,
2283                                            const struct in6_addr *prefix, int prefixlen,
2284                                            const struct in6_addr *gwaddr, int ifindex,
2285                                            unsigned int pref)
2286 {
2287         struct fib6_config cfg = {
2288                 .fc_table       = RT6_TABLE_INFO,
2289                 .fc_metric      = IP6_RT_PRIO_USER,
2290                 .fc_ifindex     = ifindex,
2291                 .fc_dst_len     = prefixlen,
2292                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_ROUTEINFO |
2293                                   RTF_UP | RTF_PREF(pref),
2294                 .fc_nlinfo.portid = 0,
2295                 .fc_nlinfo.nlh = NULL,
2296                 .fc_nlinfo.nl_net = net,
2297         };
2298
2299         cfg.fc_dst = *prefix;
2300         cfg.fc_gateway = *gwaddr;
2301
2302         /* We should treat it as a default route if prefix length is 0. */
2303         if (!prefixlen)
2304                 cfg.fc_flags |= RTF_DEFAULT;
2305
2306         ip6_route_add(&cfg);
2307
2308         return rt6_get_route_info(net, prefix, prefixlen, gwaddr, ifindex);
2309 }
2310 #endif
2311
2312 struct rt6_info *rt6_get_dflt_router(const struct in6_addr *addr, struct net_device *dev)
2313 {
2314         struct rt6_info *rt;
2315         struct fib6_table *table;
2316
2317         table = fib6_get_table(dev_net(dev), RT6_TABLE_DFLT);
2318         if (!table)
2319                 return NULL;
2320
2321         read_lock_bh(&table->tb6_lock);
2322         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2323                 if (dev == rt->dst.dev &&
2324                     ((rt->rt6i_flags & (RTF_ADDRCONF | RTF_DEFAULT)) == (RTF_ADDRCONF | RTF_DEFAULT)) &&
2325                     ipv6_addr_equal(&rt->rt6i_gateway, addr))
2326                         break;
2327         }
2328         if (rt)
2329                 dst_hold(&rt->dst);
2330         read_unlock_bh(&table->tb6_lock);
2331         return rt;
2332 }
2333
2334 struct rt6_info *rt6_add_dflt_router(const struct in6_addr *gwaddr,
2335                                      struct net_device *dev,
2336                                      unsigned int pref)
2337 {
2338         struct fib6_config cfg = {
2339                 .fc_table       = RT6_TABLE_DFLT,
2340                 .fc_metric      = IP6_RT_PRIO_USER,
2341                 .fc_ifindex     = dev->ifindex,
2342                 .fc_flags       = RTF_GATEWAY | RTF_ADDRCONF | RTF_DEFAULT |
2343                                   RTF_UP | RTF_EXPIRES | RTF_PREF(pref),
2344                 .fc_nlinfo.portid = 0,
2345                 .fc_nlinfo.nlh = NULL,
2346                 .fc_nlinfo.nl_net = dev_net(dev),
2347         };
2348
2349         cfg.fc_gateway = *gwaddr;
2350
2351         ip6_route_add(&cfg);
2352
2353         return rt6_get_dflt_router(gwaddr, dev);
2354 }
2355
2356 void rt6_purge_dflt_routers(struct net *net)
2357 {
2358         struct rt6_info *rt;
2359         struct fib6_table *table;
2360
2361         /* NOTE: Keep consistent with rt6_get_dflt_router */
2362         table = fib6_get_table(net, RT6_TABLE_DFLT);
2363         if (!table)
2364                 return;
2365
2366 restart:
2367         read_lock_bh(&table->tb6_lock);
2368         for (rt = table->tb6_root.leaf; rt; rt = rt->dst.rt6_next) {
2369                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF) &&
2370                     (!rt->rt6i_idev || rt->rt6i_idev->cnf.accept_ra != 2)) {
2371                         dst_hold(&rt->dst);
2372                         read_unlock_bh(&table->tb6_lock);
2373                         ip6_del_rt(rt);
2374                         goto restart;
2375                 }
2376         }
2377         read_unlock_bh(&table->tb6_lock);
2378 }
2379
2380 static void rtmsg_to_fib6_config(struct net *net,
2381                                  struct in6_rtmsg *rtmsg,
2382                                  struct fib6_config *cfg)
2383 {
2384         memset(cfg, 0, sizeof(*cfg));
2385
2386         cfg->fc_table = RT6_TABLE_MAIN;
2387         cfg->fc_ifindex = rtmsg->rtmsg_ifindex;
2388         cfg->fc_metric = rtmsg->rtmsg_metric;
2389         cfg->fc_expires = rtmsg->rtmsg_info;
2390         cfg->fc_dst_len = rtmsg->rtmsg_dst_len;
2391         cfg->fc_src_len = rtmsg->rtmsg_src_len;
2392         cfg->fc_flags = rtmsg->rtmsg_flags;
2393
2394         cfg->fc_nlinfo.nl_net = net;
2395
2396         cfg->fc_dst = rtmsg->rtmsg_dst;
2397         cfg->fc_src = rtmsg->rtmsg_src;
2398         cfg->fc_gateway = rtmsg->rtmsg_gateway;
2399 }
2400
2401 int ipv6_route_ioctl(struct net *net, unsigned int cmd, void __user *arg)
2402 {
2403         struct fib6_config cfg;
2404         struct in6_rtmsg rtmsg;
2405         int err;
2406
2407         switch (cmd) {
2408         case SIOCADDRT:         /* Add a route */
2409         case SIOCDELRT:         /* Delete a route */
2410                 if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2411                         return -EPERM;
2412                 err = copy_from_user(&rtmsg, arg,
2413                                      sizeof(struct in6_rtmsg));
2414                 if (err)
2415                         return -EFAULT;
2416
2417                 rtmsg_to_fib6_config(net, &rtmsg, &cfg);
2418
2419                 rtnl_lock();
2420                 switch (cmd) {
2421                 case SIOCADDRT:
2422                         err = ip6_route_add(&cfg);
2423                         break;
2424                 case SIOCDELRT:
2425                         err = ip6_route_del(&cfg);
2426                         break;
2427                 default:
2428                         err = -EINVAL;
2429                 }
2430                 rtnl_unlock();
2431
2432                 return err;
2433         }
2434
2435         return -EINVAL;
2436 }
2437
2438 /*
2439  *      Drop the packet on the floor
2440  */
2441
2442 static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
2443 {
2444         int type;
2445         struct dst_entry *dst = skb_dst(skb);
2446         switch (ipstats_mib_noroutes) {
2447         case IPSTATS_MIB_INNOROUTES:
2448                 type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
2449                 if (type == IPV6_ADDR_ANY) {
2450                         IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2451                                       IPSTATS_MIB_INADDRERRORS);
2452                         break;
2453                 }
2454                 /* FALLTHROUGH */
2455         case IPSTATS_MIB_OUTNOROUTES:
2456                 IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
2457                               ipstats_mib_noroutes);
2458                 break;
2459         }
2460         icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
2461         kfree_skb(skb);
2462         return 0;
2463 }
2464
2465 static int ip6_pkt_discard(struct sk_buff *skb)
2466 {
2467         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_INNOROUTES);
2468 }
2469
2470 static int ip6_pkt_discard_out(struct sock *sk, struct sk_buff *skb)
2471 {
2472         skb->dev = skb_dst(skb)->dev;
2473         return ip6_pkt_drop(skb, ICMPV6_NOROUTE, IPSTATS_MIB_OUTNOROUTES);
2474 }
2475
2476 static int ip6_pkt_prohibit(struct sk_buff *skb)
2477 {
2478         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_INNOROUTES);
2479 }
2480
2481 static int ip6_pkt_prohibit_out(struct sock *sk, struct sk_buff *skb)
2482 {
2483         skb->dev = skb_dst(skb)->dev;
2484         return ip6_pkt_drop(skb, ICMPV6_ADM_PROHIBITED, IPSTATS_MIB_OUTNOROUTES);
2485 }
2486
2487 /*
2488  *      Allocate a dst for local (unicast / anycast) address.
2489  */
2490
2491 struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
2492                                     const struct in6_addr *addr,
2493                                     bool anycast)
2494 {
2495         struct net *net = dev_net(idev->dev);
2496         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
2497                                             DST_NOCOUNT);
2498         if (!rt)
2499                 return ERR_PTR(-ENOMEM);
2500
2501         in6_dev_hold(idev);
2502
2503         rt->dst.flags |= DST_HOST;
2504         rt->dst.input = ip6_input;
2505         rt->dst.output = ip6_output;
2506         rt->rt6i_idev = idev;
2507
2508         rt->rt6i_flags = RTF_UP | RTF_NONEXTHOP;
2509         if (anycast)
2510                 rt->rt6i_flags |= RTF_ANYCAST;
2511         else
2512                 rt->rt6i_flags |= RTF_LOCAL;
2513
2514         rt->rt6i_gateway  = *addr;
2515         rt->rt6i_dst.addr = *addr;
2516         rt->rt6i_dst.plen = 128;
2517         rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);
2518
2519         atomic_set(&rt->dst.__refcnt, 1);
2520
2521         return rt;
2522 }
2523
2524 int ip6_route_get_saddr(struct net *net,
2525                         struct rt6_info *rt,
2526                         const struct in6_addr *daddr,
2527                         unsigned int prefs,
2528                         struct in6_addr *saddr)
2529 {
2530         struct inet6_dev *idev =
2531                 rt ? ip6_dst_idev((struct dst_entry *)rt) : NULL;
2532         int err = 0;
2533         if (rt && rt->rt6i_prefsrc.plen)
2534                 *saddr = rt->rt6i_prefsrc.addr;
2535         else
2536                 err = ipv6_dev_get_saddr(net, idev ? idev->dev : NULL,
2537                                          daddr, prefs, saddr);
2538         return err;
2539 }
2540
2541 /* remove deleted ip from prefsrc entries */
2542 struct arg_dev_net_ip {
2543         struct net_device *dev;
2544         struct net *net;
2545         struct in6_addr *addr;
2546 };
2547
2548 static int fib6_remove_prefsrc(struct rt6_info *rt, void *arg)
2549 {
2550         struct net_device *dev = ((struct arg_dev_net_ip *)arg)->dev;
2551         struct net *net = ((struct arg_dev_net_ip *)arg)->net;
2552         struct in6_addr *addr = ((struct arg_dev_net_ip *)arg)->addr;
2553
2554         if (((void *)rt->dst.dev == dev || !dev) &&
2555             rt != net->ipv6.ip6_null_entry &&
2556             ipv6_addr_equal(addr, &rt->rt6i_prefsrc.addr)) {
2557                 /* remove prefsrc entry */
2558                 rt->rt6i_prefsrc.plen = 0;
2559         }
2560         return 0;
2561 }
2562
2563 void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
2564 {
2565         struct net *net = dev_net(ifp->idev->dev);
2566         struct arg_dev_net_ip adni = {
2567                 .dev = ifp->idev->dev,
2568                 .net = net,
2569                 .addr = &ifp->addr,
2570         };
2571         fib6_clean_all(net, fib6_remove_prefsrc, &adni);
2572 }
2573
2574 #define RTF_RA_ROUTER           (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
2575 #define RTF_CACHE_GATEWAY       (RTF_GATEWAY | RTF_CACHE)
2576
2577 /* Remove routers and update dst entries when gateway turn into host. */
2578 static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
2579 {
2580         struct in6_addr *gateway = (struct in6_addr *)arg;
2581
2582         if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
2583              ((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
2584              ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
2585                 return -1;
2586         }
2587         return 0;
2588 }
2589
2590 void rt6_clean_tohost(struct net *net, struct in6_addr *gateway)
2591 {
2592         fib6_clean_all(net, fib6_clean_tohost, gateway);
2593 }
2594
2595 struct arg_dev_net {
2596         struct net_device *dev;
2597         struct net *net;
2598 };
2599
2600 static int fib6_ifdown(struct rt6_info *rt, void *arg)
2601 {
2602         const struct arg_dev_net *adn = arg;
2603         const struct net_device *dev = adn->dev;
2604
2605         if ((rt->dst.dev == dev || !dev) &&
2606             rt != adn->net->ipv6.ip6_null_entry)
2607                 return -1;
2608
2609         return 0;
2610 }
2611
2612 void rt6_ifdown(struct net *net, struct net_device *dev)
2613 {
2614         struct arg_dev_net adn = {
2615                 .dev = dev,
2616                 .net = net,
2617         };
2618
2619         fib6_clean_all(net, fib6_ifdown, &adn);
2620         icmp6_clean_all(fib6_ifdown, &adn);
2621         rt6_uncached_list_flush_dev(net, dev);
2622 }
2623
2624 struct rt6_mtu_change_arg {
2625         struct net_device *dev;
2626         unsigned int mtu;
2627 };
2628
2629 static int rt6_mtu_change_route(struct rt6_info *rt, void *p_arg)
2630 {
2631         struct rt6_mtu_change_arg *arg = (struct rt6_mtu_change_arg *) p_arg;
2632         struct inet6_dev *idev;
2633
2634         /* In IPv6 pmtu discovery is not optional,
2635            so that RTAX_MTU lock cannot disable it.
2636            We still use this lock to block changes
2637            caused by addrconf/ndisc.
2638         */
2639
2640         idev = __in6_dev_get(arg->dev);
2641         if (!idev)
2642                 return 0;
2643
2644         /* For administrative MTU increase, there is no way to discover
2645            IPv6 PMTU increase, so PMTU increase should be updated here.
2646            Since RFC 1981 doesn't include administrative MTU increase
2647            update PMTU increase is a MUST. (i.e. jumbo frame)
2648          */
2649         /*
2650            If new MTU is less than route PMTU, this new MTU will be the
2651            lowest MTU in the path, update the route PMTU to reflect PMTU
2652            decreases; if new MTU is greater than route PMTU, and the
2653            old MTU is the lowest MTU in the path, update the route PMTU
2654            to reflect the increase. In this case if the other nodes' MTU
2655            also have the lowest MTU, TOO BIG MESSAGE will be lead to
2656            PMTU discouvery.
2657          */
2658         if (rt->dst.dev == arg->dev &&
2659             !dst_metric_locked(&rt->dst, RTAX_MTU)) {
2660                 if (rt->rt6i_flags & RTF_CACHE) {
2661                         /* For RTF_CACHE with rt6i_pmtu == 0
2662                          * (i.e. a redirected route),
2663                          * the metrics of its rt->dst.from has already
2664                          * been updated.
2665                          */
2666                         if (rt->rt6i_pmtu && rt->rt6i_pmtu > arg->mtu)
2667                                 rt->rt6i_pmtu = arg->mtu;
2668                 } else if (dst_mtu(&rt->dst) >= arg->mtu ||
2669                            (dst_mtu(&rt->dst) < arg->mtu &&
2670                             dst_mtu(&rt->dst) == idev->cnf.mtu6)) {
2671                         dst_metric_set(&rt->dst, RTAX_MTU, arg->mtu);
2672                 }
2673         }
2674         return 0;
2675 }
2676
2677 void rt6_mtu_change(struct net_device *dev, unsigned int mtu)
2678 {
2679         struct rt6_mtu_change_arg arg = {
2680                 .dev = dev,
2681                 .mtu = mtu,
2682         };
2683
2684         fib6_clean_all(dev_net(dev), rt6_mtu_change_route, &arg);
2685 }
2686
2687 static const struct nla_policy rtm_ipv6_policy[RTA_MAX+1] = {
2688         [RTA_GATEWAY]           = { .len = sizeof(struct in6_addr) },
2689         [RTA_OIF]               = { .type = NLA_U32 },
2690         [RTA_IIF]               = { .type = NLA_U32 },
2691         [RTA_PRIORITY]          = { .type = NLA_U32 },
2692         [RTA_METRICS]           = { .type = NLA_NESTED },
2693         [RTA_MULTIPATH]         = { .len = sizeof(struct rtnexthop) },
2694         [RTA_PREF]              = { .type = NLA_U8 },
2695         [RTA_ENCAP_TYPE]        = { .type = NLA_U16 },
2696         [RTA_ENCAP]             = { .type = NLA_NESTED },
2697 };
2698
2699 static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
2700                               struct fib6_config *cfg)
2701 {
2702         struct rtmsg *rtm;
2703         struct nlattr *tb[RTA_MAX+1];
2704         unsigned int pref;
2705         int err;
2706
2707         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
2708         if (err < 0)
2709                 goto errout;
2710
2711         err = -EINVAL;
2712         rtm = nlmsg_data(nlh);
2713         memset(cfg, 0, sizeof(*cfg));
2714
2715         cfg->fc_table = rtm->rtm_table;
2716         cfg->fc_dst_len = rtm->rtm_dst_len;
2717         cfg->fc_src_len = rtm->rtm_src_len;
2718         cfg->fc_flags = RTF_UP;
2719         cfg->fc_protocol = rtm->rtm_protocol;
2720         cfg->fc_type = rtm->rtm_type;
2721
2722         if (rtm->rtm_type == RTN_UNREACHABLE ||
2723             rtm->rtm_type == RTN_BLACKHOLE ||
2724             rtm->rtm_type == RTN_PROHIBIT ||
2725             rtm->rtm_type == RTN_THROW)
2726                 cfg->fc_flags |= RTF_REJECT;
2727
2728         if (rtm->rtm_type == RTN_LOCAL)
2729                 cfg->fc_flags |= RTF_LOCAL;
2730
2731         if (rtm->rtm_flags & RTM_F_CLONED)
2732                 cfg->fc_flags |= RTF_CACHE;
2733
2734         cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid;
2735         cfg->fc_nlinfo.nlh = nlh;
2736         cfg->fc_nlinfo.nl_net = sock_net(skb->sk);
2737
2738         if (tb[RTA_GATEWAY]) {
2739                 cfg->fc_gateway = nla_get_in6_addr(tb[RTA_GATEWAY]);
2740                 cfg->fc_flags |= RTF_GATEWAY;
2741         }
2742
2743         if (tb[RTA_DST]) {
2744                 int plen = (rtm->rtm_dst_len + 7) >> 3;
2745
2746                 if (nla_len(tb[RTA_DST]) < plen)
2747                         goto errout;
2748
2749                 nla_memcpy(&cfg->fc_dst, tb[RTA_DST], plen);
2750         }
2751
2752         if (tb[RTA_SRC]) {
2753                 int plen = (rtm->rtm_src_len + 7) >> 3;
2754
2755                 if (nla_len(tb[RTA_SRC]) < plen)
2756                         goto errout;
2757
2758                 nla_memcpy(&cfg->fc_src, tb[RTA_SRC], plen);
2759         }
2760
2761         if (tb[RTA_PREFSRC])
2762                 cfg->fc_prefsrc = nla_get_in6_addr(tb[RTA_PREFSRC]);
2763
2764         if (tb[RTA_OIF])
2765                 cfg->fc_ifindex = nla_get_u32(tb[RTA_OIF]);
2766
2767         if (tb[RTA_PRIORITY])
2768                 cfg->fc_metric = nla_get_u32(tb[RTA_PRIORITY]);
2769
2770         if (tb[RTA_METRICS]) {
2771                 cfg->fc_mx = nla_data(tb[RTA_METRICS]);
2772                 cfg->fc_mx_len = nla_len(tb[RTA_METRICS]);
2773         }
2774
2775         if (tb[RTA_TABLE])
2776                 cfg->fc_table = nla_get_u32(tb[RTA_TABLE]);
2777
2778         if (tb[RTA_MULTIPATH]) {
2779                 cfg->fc_mp = nla_data(tb[RTA_MULTIPATH]);
2780                 cfg->fc_mp_len = nla_len(tb[RTA_MULTIPATH]);
2781         }
2782
2783         if (tb[RTA_PREF]) {
2784                 pref = nla_get_u8(tb[RTA_PREF]);
2785                 if (pref != ICMPV6_ROUTER_PREF_LOW &&
2786                     pref != ICMPV6_ROUTER_PREF_HIGH)
2787                         pref = ICMPV6_ROUTER_PREF_MEDIUM;
2788                 cfg->fc_flags |= RTF_PREF(pref);
2789         }
2790
2791         if (tb[RTA_ENCAP])
2792                 cfg->fc_encap = tb[RTA_ENCAP];
2793
2794         if (tb[RTA_ENCAP_TYPE])
2795                 cfg->fc_encap_type = nla_get_u16(tb[RTA_ENCAP_TYPE]);
2796
2797         err = 0;
2798 errout:
2799         return err;
2800 }
2801
2802 struct rt6_nh {
2803         struct rt6_info *rt6_info;
2804         struct fib6_config r_cfg;
2805         struct mx6_config mxc;
2806         struct list_head next;
2807 };
2808
2809 static void ip6_print_replace_route_err(struct list_head *rt6_nh_list)
2810 {
2811         struct rt6_nh *nh;
2812
2813         list_for_each_entry(nh, rt6_nh_list, next) {
2814                 pr_warn("IPV6: multipath route replace failed (check consistency of installed routes): %pI6 nexthop %pI6 ifi %d\n",
2815                         &nh->r_cfg.fc_dst, &nh->r_cfg.fc_gateway,
2816                         nh->r_cfg.fc_ifindex);
2817         }
2818 }
2819
2820 static int ip6_route_info_append(struct list_head *rt6_nh_list,
2821                                  struct rt6_info *rt, struct fib6_config *r_cfg)
2822 {
2823         struct rt6_nh *nh;
2824         struct rt6_info *rtnh;
2825         int err = -EEXIST;
2826
2827         list_for_each_entry(nh, rt6_nh_list, next) {
2828                 /* check if rt6_info already exists */
2829                 rtnh = nh->rt6_info;
2830
2831                 if (rtnh->dst.dev == rt->dst.dev &&
2832                     rtnh->rt6i_idev == rt->rt6i_idev &&
2833                     ipv6_addr_equal(&rtnh->rt6i_gateway,
2834                                     &rt->rt6i_gateway))
2835                         return err;
2836         }
2837
2838         nh = kzalloc(sizeof(*nh), GFP_KERNEL);
2839         if (!nh)
2840                 return -ENOMEM;
2841         nh->rt6_info = rt;
2842         err = ip6_convert_metrics(&nh->mxc, r_cfg);
2843         if (err) {
2844                 kfree(nh);
2845                 return err;
2846         }
2847         memcpy(&nh->r_cfg, r_cfg, sizeof(*r_cfg));
2848         list_add_tail(&nh->next, rt6_nh_list);
2849
2850         return 0;
2851 }
2852
2853 static int ip6_route_multipath_add(struct fib6_config *cfg)
2854 {
2855         struct fib6_config r_cfg;
2856         struct rtnexthop *rtnh;
2857         struct rt6_info *rt;
2858         struct rt6_nh *err_nh;
2859         struct rt6_nh *nh, *nh_safe;
2860         int remaining;
2861         int attrlen;
2862         int err = 1;
2863         int nhn = 0;
2864         int replace = (cfg->fc_nlinfo.nlh &&
2865                        (cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_REPLACE));
2866         LIST_HEAD(rt6_nh_list);
2867
2868         remaining = cfg->fc_mp_len;
2869         rtnh = (struct rtnexthop *)cfg->fc_mp;
2870
2871         /* Parse a Multipath Entry and build a list (rt6_nh_list) of
2872          * rt6_info structs per nexthop
2873          */
2874         while (rtnh_ok(rtnh, remaining)) {
2875                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2876                 if (rtnh->rtnh_ifindex)
2877                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2878
2879                 attrlen = rtnh_attrlen(rtnh);
2880                 if (attrlen > 0) {
2881                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2882
2883                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2884                         if (nla) {
2885                                 r_cfg.fc_gateway = nla_get_in6_addr(nla);
2886                                 r_cfg.fc_flags |= RTF_GATEWAY;
2887                         }
2888                         r_cfg.fc_encap = nla_find(attrs, attrlen, RTA_ENCAP);
2889                         nla = nla_find(attrs, attrlen, RTA_ENCAP_TYPE);
2890                         if (nla)
2891                                 r_cfg.fc_encap_type = nla_get_u16(nla);
2892                 }
2893
2894                 err = ip6_route_info_create(&r_cfg, &rt);
2895                 if (err)
2896                         goto cleanup;
2897
2898                 err = ip6_route_info_append(&rt6_nh_list, rt, &r_cfg);
2899                 if (err) {
2900                         dst_free(&rt->dst);
2901                         goto cleanup;
2902                 }
2903
2904                 rtnh = rtnh_next(rtnh, &remaining);
2905         }
2906
2907         err_nh = NULL;
2908         list_for_each_entry(nh, &rt6_nh_list, next) {
2909                 err = __ip6_ins_rt(nh->rt6_info, &cfg->fc_nlinfo, &nh->mxc);
2910                 /* nh->rt6_info is used or freed at this point, reset to NULL*/
2911                 nh->rt6_info = NULL;
2912                 if (err) {
2913                         if (replace && nhn)
2914                                 ip6_print_replace_route_err(&rt6_nh_list);
2915                         err_nh = nh;
2916                         goto add_errout;
2917                 }
2918
2919                 /* Because each route is added like a single route we remove
2920                  * these flags after the first nexthop: if there is a collision,
2921                  * we have already failed to add the first nexthop:
2922                  * fib6_add_rt2node() has rejected it; when replacing, old
2923                  * nexthops have been replaced by first new, the rest should
2924                  * be added to it.
2925                  */
2926                 cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
2927                                                      NLM_F_REPLACE);
2928                 nhn++;
2929         }
2930
2931         goto cleanup;
2932
2933 add_errout:
2934         /* Delete routes that were already added */
2935         list_for_each_entry(nh, &rt6_nh_list, next) {
2936                 if (err_nh == nh)
2937                         break;
2938                 ip6_route_del(&nh->r_cfg);
2939         }
2940
2941 cleanup:
2942         list_for_each_entry_safe(nh, nh_safe, &rt6_nh_list, next) {
2943                 if (nh->rt6_info)
2944                         dst_free(&nh->rt6_info->dst);
2945                 kfree(nh->mxc.mx);
2946                 list_del(&nh->next);
2947                 kfree(nh);
2948         }
2949
2950         return err;
2951 }
2952
2953 static int ip6_route_multipath_del(struct fib6_config *cfg)
2954 {
2955         struct fib6_config r_cfg;
2956         struct rtnexthop *rtnh;
2957         int remaining;
2958         int attrlen;
2959         int err = 1, last_err = 0;
2960
2961         remaining = cfg->fc_mp_len;
2962         rtnh = (struct rtnexthop *)cfg->fc_mp;
2963
2964         /* Parse a Multipath Entry */
2965         while (rtnh_ok(rtnh, remaining)) {
2966                 memcpy(&r_cfg, cfg, sizeof(*cfg));
2967                 if (rtnh->rtnh_ifindex)
2968                         r_cfg.fc_ifindex = rtnh->rtnh_ifindex;
2969
2970                 attrlen = rtnh_attrlen(rtnh);
2971                 if (attrlen > 0) {
2972                         struct nlattr *nla, *attrs = rtnh_attrs(rtnh);
2973
2974                         nla = nla_find(attrs, attrlen, RTA_GATEWAY);
2975                         if (nla) {
2976                                 nla_memcpy(&r_cfg.fc_gateway, nla, 16);
2977                                 r_cfg.fc_flags |= RTF_GATEWAY;
2978                         }
2979                 }
2980                 err = ip6_route_del(&r_cfg);
2981                 if (err)
2982                         last_err = err;
2983
2984                 rtnh = rtnh_next(rtnh, &remaining);
2985         }
2986
2987         return last_err;
2988 }
2989
2990 static int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh)
2991 {
2992         struct fib6_config cfg;
2993         int err;
2994
2995         err = rtm_to_fib6_config(skb, nlh, &cfg);
2996         if (err < 0)
2997                 return err;
2998
2999         if (cfg.fc_mp)
3000                 return ip6_route_multipath_del(&cfg);
3001         else
3002                 return ip6_route_del(&cfg);
3003 }
3004
3005 static int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh)
3006 {
3007         struct fib6_config cfg;
3008         int err;
3009
3010         err = rtm_to_fib6_config(skb, nlh, &cfg);
3011         if (err < 0)
3012                 return err;
3013
3014         if (cfg.fc_mp)
3015                 return ip6_route_multipath_add(&cfg);
3016         else
3017                 return ip6_route_add(&cfg);
3018 }
3019
3020 static inline size_t rt6_nlmsg_size(struct rt6_info *rt)
3021 {
3022         return NLMSG_ALIGN(sizeof(struct rtmsg))
3023                + nla_total_size(16) /* RTA_SRC */
3024                + nla_total_size(16) /* RTA_DST */
3025                + nla_total_size(16) /* RTA_GATEWAY */
3026                + nla_total_size(16) /* RTA_PREFSRC */
3027                + nla_total_size(4) /* RTA_TABLE */
3028                + nla_total_size(4) /* RTA_IIF */
3029                + nla_total_size(4) /* RTA_OIF */
3030                + nla_total_size(4) /* RTA_PRIORITY */
3031                + RTAX_MAX * nla_total_size(4) /* RTA_METRICS */
3032                + nla_total_size(sizeof(struct rta_cacheinfo))
3033                + nla_total_size(TCP_CA_NAME_MAX) /* RTAX_CC_ALGO */
3034                + nla_total_size(1) /* RTA_PREF */
3035                + lwtunnel_get_encap_size(rt->dst.lwtstate);
3036 }
3037
3038 static int rt6_fill_node(struct net *net,
3039                          struct sk_buff *skb, struct rt6_info *rt,
3040                          struct in6_addr *dst, struct in6_addr *src,
3041                          int iif, int type, u32 portid, u32 seq,
3042                          int prefix, int nowait, unsigned int flags)
3043 {
3044         u32 metrics[RTAX_MAX];
3045         struct rtmsg *rtm;
3046         struct nlmsghdr *nlh;
3047         long expires;
3048         u32 table;
3049
3050         if (prefix) {   /* user wants prefix routes only */
3051                 if (!(rt->rt6i_flags & RTF_PREFIX_RT)) {
3052                         /* success since this is not a prefix route */
3053                         return 1;
3054                 }
3055         }
3056
3057         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*rtm), flags);
3058         if (!nlh)
3059                 return -EMSGSIZE;
3060
3061         rtm = nlmsg_data(nlh);
3062         rtm->rtm_family = AF_INET6;
3063         rtm->rtm_dst_len = rt->rt6i_dst.plen;
3064         rtm->rtm_src_len = rt->rt6i_src.plen;
3065         rtm->rtm_tos = 0;
3066         if (rt->rt6i_table)
3067                 table = rt->rt6i_table->tb6_id;
3068         else
3069                 table = RT6_TABLE_UNSPEC;
3070         rtm->rtm_table = table;
3071         if (nla_put_u32(skb, RTA_TABLE, table))
3072                 goto nla_put_failure;
3073         if (rt->rt6i_flags & RTF_REJECT) {
3074                 switch (rt->dst.error) {
3075                 case -EINVAL:
3076                         rtm->rtm_type = RTN_BLACKHOLE;
3077                         break;
3078                 case -EACCES:
3079                         rtm->rtm_type = RTN_PROHIBIT;
3080                         break;
3081                 case -EAGAIN:
3082                         rtm->rtm_type = RTN_THROW;
3083                         break;
3084                 default:
3085                         rtm->rtm_type = RTN_UNREACHABLE;
3086                         break;
3087                 }
3088         }
3089         else if (rt->rt6i_flags & RTF_LOCAL)
3090                 rtm->rtm_type = RTN_LOCAL;
3091         else if (rt->dst.dev && (rt->dst.dev->flags & IFF_LOOPBACK))
3092                 rtm->rtm_type = RTN_LOCAL;
3093         else
3094                 rtm->rtm_type = RTN_UNICAST;
3095         rtm->rtm_flags = 0;
3096         if (!netif_carrier_ok(rt->dst.dev)) {
3097                 rtm->rtm_flags |= RTNH_F_LINKDOWN;
3098                 if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown)
3099                         rtm->rtm_flags |= RTNH_F_DEAD;
3100         }
3101         rtm->rtm_scope = RT_SCOPE_UNIVERSE;
3102         rtm->rtm_protocol = rt->rt6i_protocol;
3103         if (rt->rt6i_flags & RTF_DYNAMIC)
3104                 rtm->rtm_protocol = RTPROT_REDIRECT;
3105         else if (rt->rt6i_flags & RTF_ADDRCONF) {
3106                 if (rt->rt6i_flags & (RTF_DEFAULT | RTF_ROUTEINFO))
3107                         rtm->rtm_protocol = RTPROT_RA;
3108                 else
3109                         rtm->rtm_protocol = RTPROT_KERNEL;
3110         }
3111
3112         if (rt->rt6i_flags & RTF_CACHE)
3113                 rtm->rtm_flags |= RTM_F_CLONED;
3114
3115         if (dst) {
3116                 if (nla_put_in6_addr(skb, RTA_DST, dst))
3117                         goto nla_put_failure;
3118                 rtm->rtm_dst_len = 128;
3119         } else if (rtm->rtm_dst_len)
3120                 if (nla_put_in6_addr(skb, RTA_DST, &rt->rt6i_dst.addr))
3121                         goto nla_put_failure;
3122 #ifdef CONFIG_IPV6_SUBTREES
3123         if (src) {
3124                 if (nla_put_in6_addr(skb, RTA_SRC, src))
3125                         goto nla_put_failure;
3126                 rtm->rtm_src_len = 128;
3127         } else if (rtm->rtm_src_len &&
3128                    nla_put_in6_addr(skb, RTA_SRC, &rt->rt6i_src.addr))
3129                 goto nla_put_failure;
3130 #endif
3131         if (iif) {
3132 #ifdef CONFIG_IPV6_MROUTE
3133                 if (ipv6_addr_is_multicast(&rt->rt6i_dst.addr)) {
3134                         int err = ip6mr_get_route(net, skb, rtm, nowait);
3135                         if (err <= 0) {
3136                                 if (!nowait) {
3137                                         if (err == 0)
3138                                                 return 0;
3139                                         goto nla_put_failure;
3140                                 } else {
3141                                         if (err == -EMSGSIZE)
3142                                                 goto nla_put_failure;
3143                                 }
3144                         }
3145                 } else
3146 #endif
3147                         if (nla_put_u32(skb, RTA_IIF, iif))
3148                                 goto nla_put_failure;
3149         } else if (dst) {
3150                 struct in6_addr saddr_buf;
3151                 if (ip6_route_get_saddr(net, rt, dst, 0, &saddr_buf) == 0 &&
3152                     nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3153                         goto nla_put_failure;
3154         }
3155
3156         if (rt->rt6i_prefsrc.plen) {
3157                 struct in6_addr saddr_buf;
3158                 saddr_buf = rt->rt6i_prefsrc.addr;
3159                 if (nla_put_in6_addr(skb, RTA_PREFSRC, &saddr_buf))
3160                         goto nla_put_failure;
3161         }
3162
3163         memcpy(metrics, dst_metrics_ptr(&rt->dst), sizeof(metrics));
3164         if (rt->rt6i_pmtu)
3165                 metrics[RTAX_MTU - 1] = rt->rt6i_pmtu;
3166         if (rtnetlink_put_metrics(skb, metrics) < 0)
3167                 goto nla_put_failure;
3168
3169         if (rt->rt6i_flags & RTF_GATEWAY) {
3170                 if (nla_put_in6_addr(skb, RTA_GATEWAY, &rt->rt6i_gateway) < 0)
3171                         goto nla_put_failure;
3172         }
3173
3174         if (rt->dst.dev &&
3175             nla_put_u32(skb, RTA_OIF, rt->dst.dev->ifindex))
3176                 goto nla_put_failure;
3177         if (nla_put_u32(skb, RTA_PRIORITY, rt->rt6i_metric))
3178                 goto nla_put_failure;
3179
3180         expires = (rt->rt6i_flags & RTF_EXPIRES) ? rt->dst.expires - jiffies : 0;
3181
3182         if (rtnl_put_cacheinfo(skb, &rt->dst, 0, expires, rt->dst.error) < 0)
3183                 goto nla_put_failure;
3184
3185         if (nla_put_u8(skb, RTA_PREF, IPV6_EXTRACT_PREF(rt->rt6i_flags)))
3186                 goto nla_put_failure;
3187
3188         lwtunnel_fill_encap(skb, rt->dst.lwtstate);
3189
3190         nlmsg_end(skb, nlh);
3191         return 0;
3192
3193 nla_put_failure:
3194         nlmsg_cancel(skb, nlh);
3195         return -EMSGSIZE;
3196 }
3197
3198 int rt6_dump_route(struct rt6_info *rt, void *p_arg)
3199 {
3200         struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
3201         int prefix;
3202
3203         if (nlmsg_len(arg->cb->nlh) >= sizeof(struct rtmsg)) {
3204                 struct rtmsg *rtm = nlmsg_data(arg->cb->nlh);
3205                 prefix = (rtm->rtm_flags & RTM_F_PREFIX) != 0;
3206         } else
3207                 prefix = 0;
3208
3209         return rt6_fill_node(arg->net,
3210                      arg->skb, rt, NULL, NULL, 0, RTM_NEWROUTE,
3211                      NETLINK_CB(arg->cb->skb).portid, arg->cb->nlh->nlmsg_seq,
3212                      prefix, 0, NLM_F_MULTI);
3213 }
3214
3215 static int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
3216 {
3217         struct net *net = sock_net(in_skb->sk);
3218         struct nlattr *tb[RTA_MAX+1];
3219         struct rt6_info *rt;
3220         struct sk_buff *skb;
3221         struct rtmsg *rtm;
3222         struct flowi6 fl6;
3223         int err, iif = 0, oif = 0;
3224
3225         err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv6_policy);
3226         if (err < 0)
3227                 goto errout;
3228
3229         err = -EINVAL;
3230         memset(&fl6, 0, sizeof(fl6));
3231
3232         if (tb[RTA_SRC]) {
3233                 if (nla_len(tb[RTA_SRC]) < sizeof(struct in6_addr))
3234                         goto errout;
3235
3236                 fl6.saddr = *(struct in6_addr *)nla_data(tb[RTA_SRC]);
3237         }
3238
3239         if (tb[RTA_DST]) {
3240                 if (nla_len(tb[RTA_DST]) < sizeof(struct in6_addr))
3241                         goto errout;
3242
3243                 fl6.daddr = *(struct in6_addr *)nla_data(tb[RTA_DST]);
3244         }
3245
3246         if (tb[RTA_IIF])
3247                 iif = nla_get_u32(tb[RTA_IIF]);
3248
3249         if (tb[RTA_OIF])
3250                 oif = nla_get_u32(tb[RTA_OIF]);
3251
3252         if (tb[RTA_MARK])
3253                 fl6.flowi6_mark = nla_get_u32(tb[RTA_MARK]);
3254
3255         if (iif) {
3256                 struct net_device *dev;
3257                 int flags = 0;
3258
3259                 dev = __dev_get_by_index(net, iif);
3260                 if (!dev) {
3261                         err = -ENODEV;
3262                         goto errout;
3263                 }
3264
3265                 fl6.flowi6_iif = iif;
3266
3267                 if (!ipv6_addr_any(&fl6.saddr))
3268                         flags |= RT6_LOOKUP_F_HAS_SADDR;
3269
3270                 rt = (struct rt6_info *)ip6_route_input_lookup(net, dev, &fl6,
3271                                                                flags);
3272         } else {
3273                 fl6.flowi6_oif = oif;
3274
3275                 rt = (struct rt6_info *)ip6_route_output(net, NULL, &fl6);
3276         }
3277
3278         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
3279         if (!skb) {
3280                 ip6_rt_put(rt);
3281                 err = -ENOBUFS;
3282                 goto errout;
3283         }
3284
3285         /* Reserve room for dummy headers, this skb can pass
3286            through good chunk of routing engine.
3287          */
3288         skb_reset_mac_header(skb);
3289         skb_reserve(skb, MAX_HEADER + sizeof(struct ipv6hdr));
3290
3291         skb_dst_set(skb, &rt->dst);
3292
3293         err = rt6_fill_node(net, skb, rt, &fl6.daddr, &fl6.saddr, iif,
3294                             RTM_NEWROUTE, NETLINK_CB(in_skb).portid,
3295                             nlh->nlmsg_seq, 0, 0, 0);
3296         if (err < 0) {
3297                 kfree_skb(skb);
3298                 goto errout;
3299         }
3300
3301         err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3302 errout:
3303         return err;
3304 }
3305
3306 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info)
3307 {
3308         struct sk_buff *skb;
3309         struct net *net = info->nl_net;
3310         u32 seq;
3311         int err;
3312
3313         err = -ENOBUFS;
3314         seq = info->nlh ? info->nlh->nlmsg_seq : 0;
3315
3316         skb = nlmsg_new(rt6_nlmsg_size(rt), gfp_any());
3317         if (!skb)
3318                 goto errout;
3319
3320         err = rt6_fill_node(net, skb, rt, NULL, NULL, 0,
3321                                 event, info->portid, seq, 0, 0, 0);
3322         if (err < 0) {
3323                 /* -EMSGSIZE implies BUG in rt6_nlmsg_size() */
3324                 WARN_ON(err == -EMSGSIZE);
3325                 kfree_skb(skb);
3326                 goto errout;
3327         }
3328         rtnl_notify(skb, net, info->portid, RTNLGRP_IPV6_ROUTE,
3329                     info->nlh, gfp_any());
3330         return;
3331 errout:
3332         if (err < 0)
3333                 rtnl_set_sk_err(net, RTNLGRP_IPV6_ROUTE, err);
3334 }
3335
3336 static int ip6_route_dev_notify(struct notifier_block *this,
3337                                 unsigned long event, void *ptr)
3338 {
3339         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3340         struct net *net = dev_net(dev);
3341
3342         if (event == NETDEV_REGISTER && (dev->flags & IFF_LOOPBACK)) {
3343                 net->ipv6.ip6_null_entry->dst.dev = dev;
3344                 net->ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(dev);
3345 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3346                 net->ipv6.ip6_prohibit_entry->dst.dev = dev;
3347                 net->ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(dev);
3348                 net->ipv6.ip6_blk_hole_entry->dst.dev = dev;
3349                 net->ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(dev);
3350 #endif
3351         }
3352
3353         return NOTIFY_OK;
3354 }
3355
3356 /*
3357  *      /proc
3358  */
3359
3360 #ifdef CONFIG_PROC_FS
3361
3362 static const struct file_operations ipv6_route_proc_fops = {
3363         .owner          = THIS_MODULE,
3364         .open           = ipv6_route_open,
3365         .read           = seq_read,
3366         .llseek         = seq_lseek,
3367         .release        = seq_release_net,
3368 };
3369
3370 static int rt6_stats_seq_show(struct seq_file *seq, void *v)
3371 {
3372         struct net *net = (struct net *)seq->private;
3373         seq_printf(seq, "%04x %04x %04x %04x %04x %04x %04x\n",
3374                    net->ipv6.rt6_stats->fib_nodes,
3375                    net->ipv6.rt6_stats->fib_route_nodes,
3376                    net->ipv6.rt6_stats->fib_rt_alloc,
3377                    net->ipv6.rt6_stats->fib_rt_entries,
3378                    net->ipv6.rt6_stats->fib_rt_cache,
3379                    dst_entries_get_slow(&net->ipv6.ip6_dst_ops),
3380                    net->ipv6.rt6_stats->fib_discarded_routes);
3381
3382         return 0;
3383 }
3384
3385 static int rt6_stats_seq_open(struct inode *inode, struct file *file)
3386 {
3387         return single_open_net(inode, file, rt6_stats_seq_show);
3388 }
3389
3390 static const struct file_operations rt6_stats_seq_fops = {
3391         .owner   = THIS_MODULE,
3392         .open    = rt6_stats_seq_open,
3393         .read    = seq_read,
3394         .llseek  = seq_lseek,
3395         .release = single_release_net,
3396 };
3397 #endif  /* CONFIG_PROC_FS */
3398
3399 #ifdef CONFIG_SYSCTL
3400
3401 static
3402 int ipv6_sysctl_rtcache_flush(struct ctl_table *ctl, int write,
3403                               void __user *buffer, size_t *lenp, loff_t *ppos)
3404 {
3405         struct net *net;
3406         int delay;
3407         if (!write)
3408                 return -EINVAL;
3409
3410         net = (struct net *)ctl->extra1;
3411         delay = net->ipv6.sysctl.flush_delay;
3412         proc_dointvec(ctl, write, buffer, lenp, ppos);
3413         fib6_run_gc(delay <= 0 ? 0 : (unsigned long)delay, net, delay > 0);
3414         return 0;
3415 }
3416
3417 struct ctl_table ipv6_route_table_template[] = {
3418         {
3419                 .procname       =       "flush",
3420                 .data           =       &init_net.ipv6.sysctl.flush_delay,
3421                 .maxlen         =       sizeof(int),
3422                 .mode           =       0200,
3423                 .proc_handler   =       ipv6_sysctl_rtcache_flush
3424         },
3425         {
3426                 .procname       =       "gc_thresh",
3427                 .data           =       &ip6_dst_ops_template.gc_thresh,
3428                 .maxlen         =       sizeof(int),
3429                 .mode           =       0644,
3430                 .proc_handler   =       proc_dointvec,
3431         },
3432         {
3433                 .procname       =       "max_size",
3434                 .data           =       &init_net.ipv6.sysctl.ip6_rt_max_size,
3435                 .maxlen         =       sizeof(int),
3436                 .mode           =       0644,
3437                 .proc_handler   =       proc_dointvec,
3438         },
3439         {
3440                 .procname       =       "gc_min_interval",
3441                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3442                 .maxlen         =       sizeof(int),
3443                 .mode           =       0644,
3444                 .proc_handler   =       proc_dointvec_jiffies,
3445         },
3446         {
3447                 .procname       =       "gc_timeout",
3448                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_timeout,
3449                 .maxlen         =       sizeof(int),
3450                 .mode           =       0644,
3451                 .proc_handler   =       proc_dointvec_jiffies,
3452         },
3453         {
3454                 .procname       =       "gc_interval",
3455                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_interval,
3456                 .maxlen         =       sizeof(int),
3457                 .mode           =       0644,
3458                 .proc_handler   =       proc_dointvec_jiffies,
3459         },
3460         {
3461                 .procname       =       "gc_elasticity",
3462                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_elasticity,
3463                 .maxlen         =       sizeof(int),
3464                 .mode           =       0644,
3465                 .proc_handler   =       proc_dointvec,
3466         },
3467         {
3468                 .procname       =       "mtu_expires",
3469                 .data           =       &init_net.ipv6.sysctl.ip6_rt_mtu_expires,
3470                 .maxlen         =       sizeof(int),
3471                 .mode           =       0644,
3472                 .proc_handler   =       proc_dointvec_jiffies,
3473         },
3474         {
3475                 .procname       =       "min_adv_mss",
3476                 .data           =       &init_net.ipv6.sysctl.ip6_rt_min_advmss,
3477                 .maxlen         =       sizeof(int),
3478                 .mode           =       0644,
3479                 .proc_handler   =       proc_dointvec,
3480         },
3481         {
3482                 .procname       =       "gc_min_interval_ms",
3483                 .data           =       &init_net.ipv6.sysctl.ip6_rt_gc_min_interval,
3484                 .maxlen         =       sizeof(int),
3485                 .mode           =       0644,
3486                 .proc_handler   =       proc_dointvec_ms_jiffies,
3487         },
3488         { }
3489 };
3490
3491 struct ctl_table * __net_init ipv6_route_sysctl_init(struct net *net)
3492 {
3493         struct ctl_table *table;
3494
3495         table = kmemdup(ipv6_route_table_template,
3496                         sizeof(ipv6_route_table_template),
3497                         GFP_KERNEL);
3498
3499         if (table) {
3500                 table[0].data = &net->ipv6.sysctl.flush_delay;
3501                 table[0].extra1 = net;
3502                 table[1].data = &net->ipv6.ip6_dst_ops.gc_thresh;
3503                 table[2].data = &net->ipv6.sysctl.ip6_rt_max_size;
3504                 table[3].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3505                 table[4].data = &net->ipv6.sysctl.ip6_rt_gc_timeout;
3506                 table[5].data = &net->ipv6.sysctl.ip6_rt_gc_interval;
3507                 table[6].data = &net->ipv6.sysctl.ip6_rt_gc_elasticity;
3508                 table[7].data = &net->ipv6.sysctl.ip6_rt_mtu_expires;
3509                 table[8].data = &net->ipv6.sysctl.ip6_rt_min_advmss;
3510                 table[9].data = &net->ipv6.sysctl.ip6_rt_gc_min_interval;
3511
3512                 /* Don't export sysctls to unprivileged users */
3513                 if (net->user_ns != &init_user_ns)
3514                         table[0].procname = NULL;
3515         }
3516
3517         return table;
3518 }
3519 #endif
3520
3521 static int __net_init ip6_route_net_init(struct net *net)
3522 {
3523         int ret = -ENOMEM;
3524
3525         memcpy(&net->ipv6.ip6_dst_ops, &ip6_dst_ops_template,
3526                sizeof(net->ipv6.ip6_dst_ops));
3527
3528         if (dst_entries_init(&net->ipv6.ip6_dst_ops) < 0)
3529                 goto out_ip6_dst_ops;
3530
3531         net->ipv6.ip6_null_entry = kmemdup(&ip6_null_entry_template,
3532                                            sizeof(*net->ipv6.ip6_null_entry),
3533                                            GFP_KERNEL);
3534         if (!net->ipv6.ip6_null_entry)
3535                 goto out_ip6_dst_entries;
3536         net->ipv6.ip6_null_entry->dst.path =
3537                 (struct dst_entry *)net->ipv6.ip6_null_entry;
3538         net->ipv6.ip6_null_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3539         dst_init_metrics(&net->ipv6.ip6_null_entry->dst,
3540                          ip6_template_metrics, true);
3541
3542 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3543         net->ipv6.ip6_prohibit_entry = kmemdup(&ip6_prohibit_entry_template,
3544                                                sizeof(*net->ipv6.ip6_prohibit_entry),
3545                                                GFP_KERNEL);
3546         if (!net->ipv6.ip6_prohibit_entry)
3547                 goto out_ip6_null_entry;
3548         net->ipv6.ip6_prohibit_entry->dst.path =
3549                 (struct dst_entry *)net->ipv6.ip6_prohibit_entry;
3550         net->ipv6.ip6_prohibit_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3551         dst_init_metrics(&net->ipv6.ip6_prohibit_entry->dst,
3552                          ip6_template_metrics, true);
3553
3554         net->ipv6.ip6_blk_hole_entry = kmemdup(&ip6_blk_hole_entry_template,
3555                                                sizeof(*net->ipv6.ip6_blk_hole_entry),
3556                                                GFP_KERNEL);
3557         if (!net->ipv6.ip6_blk_hole_entry)
3558                 goto out_ip6_prohibit_entry;
3559         net->ipv6.ip6_blk_hole_entry->dst.path =
3560                 (struct dst_entry *)net->ipv6.ip6_blk_hole_entry;
3561         net->ipv6.ip6_blk_hole_entry->dst.ops = &net->ipv6.ip6_dst_ops;
3562         dst_init_metrics(&net->ipv6.ip6_blk_hole_entry->dst,
3563                          ip6_template_metrics, true);
3564 #endif
3565
3566         net->ipv6.sysctl.flush_delay = 0;
3567         net->ipv6.sysctl.ip6_rt_max_size = 4096;
3568         net->ipv6.sysctl.ip6_rt_gc_min_interval = HZ / 2;
3569         net->ipv6.sysctl.ip6_rt_gc_timeout = 60*HZ;
3570         net->ipv6.sysctl.ip6_rt_gc_interval = 30*HZ;
3571         net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
3572         net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
3573         net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
3574
3575         net->ipv6.ip6_rt_gc_expire = 30*HZ;
3576
3577         ret = 0;
3578 out:
3579         return ret;
3580
3581 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3582 out_ip6_prohibit_entry:
3583         kfree(net->ipv6.ip6_prohibit_entry);
3584 out_ip6_null_entry:
3585         kfree(net->ipv6.ip6_null_entry);
3586 #endif
3587 out_ip6_dst_entries:
3588         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3589 out_ip6_dst_ops:
3590         goto out;
3591 }
3592
3593 static void __net_exit ip6_route_net_exit(struct net *net)
3594 {
3595         kfree(net->ipv6.ip6_null_entry);
3596 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3597         kfree(net->ipv6.ip6_prohibit_entry);
3598         kfree(net->ipv6.ip6_blk_hole_entry);
3599 #endif
3600         dst_entries_destroy(&net->ipv6.ip6_dst_ops);
3601 }
3602
3603 static int __net_init ip6_route_net_init_late(struct net *net)
3604 {
3605 #ifdef CONFIG_PROC_FS
3606         proc_create("ipv6_route", 0, net->proc_net, &ipv6_route_proc_fops);
3607         proc_create("rt6_stats", S_IRUGO, net->proc_net, &rt6_stats_seq_fops);
3608 #endif
3609         return 0;
3610 }
3611
3612 static void __net_exit ip6_route_net_exit_late(struct net *net)
3613 {
3614 #ifdef CONFIG_PROC_FS
3615         remove_proc_entry("ipv6_route", net->proc_net);
3616         remove_proc_entry("rt6_stats", net->proc_net);
3617 #endif
3618 }
3619
3620 static struct pernet_operations ip6_route_net_ops = {
3621         .init = ip6_route_net_init,
3622         .exit = ip6_route_net_exit,
3623 };
3624
3625 static int __net_init ipv6_inetpeer_init(struct net *net)
3626 {
3627         struct inet_peer_base *bp = kmalloc(sizeof(*bp), GFP_KERNEL);
3628
3629         if (!bp)
3630                 return -ENOMEM;
3631         inet_peer_base_init(bp);
3632         net->ipv6.peers = bp;
3633         return 0;
3634 }
3635
3636 static void __net_exit ipv6_inetpeer_exit(struct net *net)
3637 {
3638         struct inet_peer_base *bp = net->ipv6.peers;
3639
3640         net->ipv6.peers = NULL;
3641         inetpeer_invalidate_tree(bp);
3642         kfree(bp);
3643 }
3644
3645 static struct pernet_operations ipv6_inetpeer_ops = {
3646         .init   =       ipv6_inetpeer_init,
3647         .exit   =       ipv6_inetpeer_exit,
3648 };
3649
3650 static struct pernet_operations ip6_route_net_late_ops = {
3651         .init = ip6_route_net_init_late,
3652         .exit = ip6_route_net_exit_late,
3653 };
3654
3655 static struct notifier_block ip6_route_dev_notifier = {
3656         .notifier_call = ip6_route_dev_notify,
3657         .priority = 0,
3658 };
3659
3660 int __init ip6_route_init(void)
3661 {
3662         int ret;
3663         int cpu;
3664
3665         ret = -ENOMEM;
3666         ip6_dst_ops_template.kmem_cachep =
3667                 kmem_cache_create("ip6_dst_cache", sizeof(struct rt6_info), 0,
3668                                   SLAB_HWCACHE_ALIGN, NULL);
3669         if (!ip6_dst_ops_template.kmem_cachep)
3670                 goto out;
3671
3672         ret = dst_entries_init(&ip6_dst_blackhole_ops);
3673         if (ret)
3674                 goto out_kmem_cache;
3675
3676         ret = register_pernet_subsys(&ipv6_inetpeer_ops);
3677         if (ret)
3678                 goto out_dst_entries;
3679
3680         ret = register_pernet_subsys(&ip6_route_net_ops);
3681         if (ret)
3682                 goto out_register_inetpeer;
3683
3684         ip6_dst_blackhole_ops.kmem_cachep = ip6_dst_ops_template.kmem_cachep;
3685
3686         /* Registering of the loopback is done before this portion of code,
3687          * the loopback reference in rt6_info will not be taken, do it
3688          * manually for init_net */
3689         init_net.ipv6.ip6_null_entry->dst.dev = init_net.loopback_dev;
3690         init_net.ipv6.ip6_null_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3691   #ifdef CONFIG_IPV6_MULTIPLE_TABLES
3692         init_net.ipv6.ip6_prohibit_entry->dst.dev = init_net.loopback_dev;
3693         init_net.ipv6.ip6_prohibit_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3694         init_net.ipv6.ip6_blk_hole_entry->dst.dev = init_net.loopback_dev;
3695         init_net.ipv6.ip6_blk_hole_entry->rt6i_idev = in6_dev_get(init_net.loopback_dev);
3696   #endif
3697         ret = fib6_init();
3698         if (ret)
3699                 goto out_register_subsys;
3700
3701         ret = xfrm6_init();
3702         if (ret)
3703                 goto out_fib6_init;
3704
3705         ret = fib6_rules_init();
3706         if (ret)
3707                 goto xfrm6_init;
3708
3709         ret = register_pernet_subsys(&ip6_route_net_late_ops);
3710         if (ret)
3711                 goto fib6_rules_init;
3712
3713         ret = -ENOBUFS;
3714         if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL, NULL) ||
3715             __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL, NULL) ||
3716             __rtnl_register(PF_INET6, RTM_GETROUTE, inet6_rtm_getroute, NULL, NULL))
3717                 goto out_register_late_subsys;
3718
3719         ret = register_netdevice_notifier(&ip6_route_dev_notifier);
3720         if (ret)
3721                 goto out_register_late_subsys;
3722
3723         for_each_possible_cpu(cpu) {
3724                 struct uncached_list *ul = per_cpu_ptr(&rt6_uncached_list, cpu);
3725
3726                 INIT_LIST_HEAD(&ul->head);
3727                 spin_lock_init(&ul->lock);
3728         }
3729
3730 out:
3731         return ret;
3732
3733 out_register_late_subsys:
3734         unregister_pernet_subsys(&ip6_route_net_late_ops);
3735 fib6_rules_init:
3736         fib6_rules_cleanup();
3737 xfrm6_init:
3738         xfrm6_fini();
3739 out_fib6_init:
3740         fib6_gc_cleanup();
3741 out_register_subsys:
3742         unregister_pernet_subsys(&ip6_route_net_ops);
3743 out_register_inetpeer:
3744         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3745 out_dst_entries:
3746         dst_entries_destroy(&ip6_dst_blackhole_ops);
3747 out_kmem_cache:
3748         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3749         goto out;
3750 }
3751
3752 void ip6_route_cleanup(void)
3753 {
3754         unregister_netdevice_notifier(&ip6_route_dev_notifier);
3755         unregister_pernet_subsys(&ip6_route_net_late_ops);
3756         fib6_rules_cleanup();
3757         xfrm6_fini();
3758         fib6_gc_cleanup();
3759         unregister_pernet_subsys(&ipv6_inetpeer_ops);
3760         unregister_pernet_subsys(&ip6_route_net_ops);
3761         dst_entries_destroy(&ip6_dst_blackhole_ops);
3762         kmem_cache_destroy(ip6_dst_ops_template.kmem_cachep);
3763 }